Mindbender Anwers

Well most of them... and some you will see are disputed. So if you have a valid alternative explanation (or just feel somebody's explanation is wrong!) email us and we will include your answer.

1

Without lifting pen from paper join these dots with four straight lines:

 

Answer submitted by Mike Bosch
2 A man and his son were admitted unconscious to a local Casualty (Accident and Emergency) department after a car crash. The Casualty Doctor on duty took one look at them and said that they although they had the skills somebody else would have to deal with them. Why was this?

The Doctor was his wife. 
3 You have nine ball-bearings, all of the same size but one slightly heavier than the others, though not enough to be detected by holding them. You have some balance scales and are allowed to do only two weighings of any number of ball bearings. How do you find the heavy one?

Place the ball bearings in a 3 x 3 grid and label each ball bearing according to its position in the grid, A1, A2, A3, B1, etc. You are allowed two weighings so compare the weights of any two rows (the 3 ball bearing in that row) and note which row is the heavier (if any). Replace the ball bearings and then as with the rows compare the weight of any two columns. note which is the heavier column. Replace the ball bearings. The heavier row and column will give the position of heavy ball bearing in the grid. If either weighing is a perfect balance then you know the heavier ball bearing is the row or column you didn't weigh.

Alternative:

Put any 3 balls on each side of the scale. This will tell you which group of 3 has the heavy ball. For the second weighing, put 1 of the heavy group on each side of the scale. If the scale is balanced, the heavy ball is the one you didn't weigh. This way you don't need to keep track of which ball is which.

Sent in by Garrett Roberts

4 So you can spell coke, joke, poke but how do you spell the white of an egg?

"Albumen" - Which is the white of an egg. Did you think it was "yolk"

Sent in by Renai McLean
5 Name a commonly used used four-letter word ending in E-N-Y (If you find this easy it is because you are seeing it writing. Try it on someone verbally and see them suffer)

Deny... it if you can!!
6 A farmer has to transport a fox, a goose and a sack of grain across a river. The boat is so small that there is room only for him and one of the others at a time, but if he leaves the fox and goose together the fox will kill the goose, and if the goose and the sack of grain are left together the goose will eat the grain. How does he get them all over?

1st journey takes goose only, leaving fox and grain. Returns leaving goose on other side.
2nd journey takes fox over, leave fox on other side, returns with goose.
3rd journey takes grain over leaving on the other side with fox. Returns and picks up goose again taking it over on the 4th journey.

Alternatives

  • Geese can swim so takes fox over first goose tethered and swimming behind each journey, returns picks up grain. (2 Journeys)
  • Fox and grain in boat, both farmer and goose swim, farmer pushing boat. :-) (1 Journey!!)

    		•
    7 Place three silver coins and three copper coins in a row like this:

    6 coins in row SSSBBB

    Moving only two adjoining coins at a time can you in three moves, change it to this:

    6 Coins in row SBSBSB

    Emphasis on 'adjoining' and not to think too laterally!!

    8 A water lily growing in a circular pond doubles in size every day. It takes thirty days to cover the whole pond. How long does it take to cover half the pond?

    29
    9 There was a good job going in the office and the boss could not decide which of the three candidates should have it, each of them being worthy of it and all of them very bright indeed. So he set them a problem and the one who solved it would get the job. He showed them five discs, three black and two white and said: ‘I’m going to put a disc on the forehead of each of you. You will be able to see the others discs but not your own. There will be no talking. By pure deduction you will have to work out what colour disc you have, and the one who does so gets the job.’ He withheld the two white discs and put a black one on each of them. After a time one of the men stepped forward and successfully claimed the job. How did he figure out that he had a black disc on?

    Call the candidates A, B and C... A gets the job through the following reasoning:-
    If I had a white disc, then B would have gone into the office already, because he would have figured to himself,

    "Well, I(B) can see A has white, which means if I(B) had white also, by now C would have figured that he can see two whites, that automatically makes me a black, so I must have the black marker because C isn't doing that."

    And with B not doing that it told A he had a black marker.

    Sent in by Jamie Salisbury

    #9 could also be: The first man saw that, the boss had no preferance, than he would know that putting a white disk on his head and black disks on the other mens heads would be unfair and would mean that all men were not solving the same puzzle. (So two men were seeing two other men: one wearing black and the other wearing white while one man saw two men- both wearing black) By forcing one man to solve one puzzle and two other men solving a copletely different puzzle, the boss would have been unfair, and he knew that the boss would not and could not do that because he had no preferance. So because he knew that the boss would not be unfair and put a different color on one mans head than the others he could know that they all had the same color, and seeing that the other two men were wearing black, knew that he too was wearing black. (He could even solve this puzzle without observing the two other mens disks because he knew that they were all wearing the same color which meant that they were all wearing black because there were only two white and three men.)

    Sent in by Robert Ehrlich
    10 Spot the error in this: ‘There was a taxi outside a hotel. A man came out, hit the taxi driver on the head, took all the money out of the meter and started to run off, only to be rugby-tackled by the commissionaire.’

    The meter of a taxi does not contain money; it is only a timer. Children living in towns or cities without many taxis probably won't know this

    Sent in by Renai McLean
    11 If you divide £100 between a certain number of people, how many people are there and how much does each get? (Study the question, the answer is there.)

    There are two people and each gets £50.  If there were more than two people, the question should be phrased ". . .divide £100 AMONG a certain number. . . " "Between" is only used for two.

    Sent in by Renai McLean
    12 Driving one stormy night from Birmingham to a small town he had never visited before, a motorist is lost when he comes to a deserted crossroads. Unfortunately the wind had blown the signpost right out of the ground, but being a bright chap he figures out which is the right road to take. How does he do it?

    He re-posts the sign, aligning it by pointing the "Birmingham" part back the way he came.

    Sent in by Renai McLean

    #12 is incorrect because: The question does not state that the sign had anything about burmingham(which as i can guess is Burmingham, Alabama) [Ed: Try Birmingham in the UK!] he would observe where the hole for the sign was and then reason that, since he was in the United States, know which way the sign faced because it is placed on the right side of the road, and if an intersection had four roads, the hole would be in one of the four corners, which means it could only belong to one of the two roads that met at that corner, assuming that they were two way roads. He knew that since he was in the U.S. and people drove on the right side of the road, the sign belonged to the road in which the right side was touching at the corner. Then he would place it were it went and know where he was going.

    Sent in by Robert Ehrlich
    13 Another motorist equally lost came to a fork in the road. There was no signpost so he had to ask at a house which was the correct fork to take him to his destination. In the house were two brothers, one of whom always told the truth and other who always lied. When one of them (he didn’t know which) came to the door he could ask him only one question. What is the single question he could ask which would ensure he found out the right road?

    I've heard ones like this before, so I'm sure this one is right.  Ask  "Which way would HE [the other brother] tell me to go, to get to. . . ?"  Then go the other way.  Either the motorist is talking to the lying brother who knows the honest brother would say to go in direction A and therefore the lying brother would lie and say the honest brother would say to go in direction B; or he is talking to the honest brother who would honestly report that his brother, who lies, would say to go in direction B (which would be a lie, so go in direction A).

    Sent in by Renai McLean

    I'm afraid that the answer for # 13 is incorrect!!!  The question states that the motorist can ask only one question.  But it does not state the number of times it can be asked.  Therefore the question that the motorist must ask the brother is "Which is the right road?"  The first time meaning left vs. right, the second time wrong vs. right.  The riddle does not state that the questions cannot be specified, the motorist can tell the brother where he is trying to get to, etc. The brother who always lies would say that the "right" (vs. left) road would be the left road!! Again: "Which is the right road?"

    Sent in by Bradley Howard

    the answers stated are both incorrect... the person should ask the following. "if i were to ask the other person, which way would he tell me to go?". If he asked the the truth teller, then the truth teller would say the truth, in that the liar person would lie and say the wrong way, so he would say the wrong way as well. So you would choose the opposite. If you asked the liar, since the truth teller would say the right way he must lie so the liar will say the opposite of that as well which of course is the wrong way. In either case they will both point to the wrong way. (Though for different reasons)

    Sent in by William Volterman

    14 When Gilbert was eleven his mother put him into an orphanage. True or false?

    False (if he has a mother he is not technically an orphan)

    Even if a kid does have a parent, I hate to say this but sometimes they still give their kids to an orphanage. because of money problems, they can't take care of you)

    [ED: So it is still an orphanage?]

    Alternative by Trista Star
    15 A person who picks up cigarette butts from the streets finds that he can roll a new cigarette from the tobacco of seven butts. One Saturday he picks up forty-nine butts and on the Sunday decides to smoke all the cigarettes he can make from them. How many cigarettes did he smoke?

    8 (He makes 7 new cigarettes from the 49 butts found, but after smoking these this creates 7 new butts so he can make another one.)
    16 ‘The vicar chose The Immaculate Conception as the theme for his sermon. He spoke fascinatingly on this subject of the birth of Christ. A total of £12.40 was taken at the collection afterwards.’ What is wrong with that?

    Immaculate conception refers to the conception of Mary and not Jesus.

    Sent in by Renai McLean

    Compiled from various sources:
    Immaculate Conception
    Roman Catholic belief that from the first instant of its creation, the soul of the Virgin Mary was free from original sin; Not to be confused with that of the Virgin Birth, which holds that Jesus Christ was born of a virgin mother. 

    Original sin
    is the idea that the sinful choice Adam made in the Garden of Eden is inherited at conception by everybody born and can only be removed by the sacraments of the church. From this arose the concept of Mary's immaculate conception. By God's choice Mary did not inherit the original sin in order that she be a suitable mother for Jesus.  
    17 Supposing you are captain of a ship and it has three red funnels and it leaves New York on a Tuesday and gets to Southampton on Saturday and on the return trip reaches New York on Thursday, what is the name of the captain of the ship. 

    All right, you got it but try it on one person - not a group, otherwise someone will cotton on - it’s astounding that you can repeat it over and over again and your victim still won’t get it.

    You
    18 An elm tree was swaying in the wind. It had eight branches and on each tree branch were eight acorns. The wind blew an acorn off each branch. How many are left?

    None- (acorns don't grow on elms..)

    I disagree with the answer to number 18. The answer is actually 56 (8x8 - 8) regardless of the fact that acorns don't grow on elm trees. The question states that there are acorns on the elms branches, so there are! If the question was how many acorns were still growing on the branches then it would work! Great pages by the way!

    Sent in by Darren Neely

    #18 both answers are incorrect because:
    i agree that the question clearly stated that acorns were infact growing on an elm tree, so you cant say they weren't. However, the answer 56 is also wrong because, although the acorns were blown off the tree, that doesn't mean they are not IN EXISTANCE, which is my interpretation of there, so the correct answer would be 64 (8x8)

    Sent in by Robert Ehrlich
    19 A middle-aged brother and sister were host and hostess at a party. A youth pointed to them and told someone that the host was his uncle. ‘I think your aunt is a charming person.’ Said the other. ‘That’s not my aunt.’ Said the young man. How come?

    You assume 'brother and sister' but in this case it is the brother from one family and a sister from another.

    "This is the solution I came up with, and I think it works as well:  The host brother got married to a woman who had siblings.  At least one of the siblings had children, one of whom is the youth at the party"

    Sent in by Renai McLean.

    The middle aged brother is the young man's uncle, so the middle aged sister must be his mother

    Sent in by Robert Gowland

    The brother is a monk, and the sister is a nun (or a matron)

    Sent in by Robert Burbidge
    20 There is a rope ladder hanging over the side of a ship. Each of the rungs of the ladder are a metre apart. The tide rises at the rate of 80 centimetres an hour. How many rungs are covered after four hours?

    The same as before... the ship floats so rises with the tide.
    21 A boy who lived on the twenty-first storey used to go down in the lift each morning to go to school and when he came home he would take the lift up to the tenth floor and walk the rest. Why?

    Might it be that he is too short to reach past the "10" button?

    Sentin by Renai McLean

    The elevator may only go up to floor ten, but has stairs going up to floor 21. (Some apartments are like this, because when they were first built they only had a certain # of stories, and were then added onto later, but only the stairs were expanded because an elevator is more expensive.)

    Sent in by Hannah Belitz

    I don't agree that he is not tall enough to reach the 21st button. I think that because of the way it is worded he no longer lives on the 21 floor and he now lives on the 10th floor. The operative words being, A boy who LIVED on the twenty-first story USED to go down the lift each morning. Now he only takes the lift to the 10th floor because that is where he now lives.

    Sent in by Chelcie Guerra

    #21 the first answer is correct but the second answer is incorrect because: You say that the boy rode down the elevator from the twenty-first floor and back up to the tenth, because the eleveator only went up to 10. But the question clearly states that the boy rode the elevator down from the twenty-first floor, so that proves that the 11-21st floors could be reached by the elevator. the third answer is also incorrect because the question is always in the past tense. He USED to go down from the 21st floor to school and when he came home, he WOULD go to the tenth floor. It never says the word NOW as that person "implied". Their answer is also wrong because the way the question was worded, he did the same routine every day. So it would be absourd to say that he moved twice a day. He would have to move twice a day because eventually he would have to go back upstairs to the 21st floor to start the whole routine over again.

    Sent in by Robert Ehrlich
    22 Here’s one for racing experts: what’s the longest race in the flat season?

    Flat racing in the UK used to be run only between late March and early November, prior to the advent of all weather racing. The flat season on grass however still is regarded as having the prestigious races and opens with the Spring meeting at Doncaster, and closes in the first week of November with the November Handicap, again at Doncaster. The shortest races for thoroughbreds in the UK are run over five furlongs (5/8 mile) and the longest is two and three quarters of a mile. This exceptional test of stamina is run at Royal Ascot each year. 

    BUT the longest UK race in the flat season is the four-and-a-half mile long Grand National in April.
    23

    Move one short line to make this correct:

      5 + 5 + 1 = 546

    5 + 5 - 1 = 54/6

    Alternatives:

    You could take off the vertical line from one of the plus signs and cross it over the equals sign. I.e. the 'does-not-equal sign'. Therefore 5 - 5 + 1 does not equal 546

    Sent in by Katy Sheen

    Hi, I love these puzzles - figured some out, got stumped by others.  I wanted to suggest an alternative answer to puzzle number 23. My solution is to restructure the first plus sign to turn it into the number four (by taking the right hand 'arm' of the plus sign and placing it on the diagonal on the left  - see the number four in 546).  This would give you 545 + 1 = 546.

    Sent in by Paula Roy

    My solution is to take the upper-left diagonal line of the '4' in 546 to make a 'plus' sign. That would make 5+5+1=5+6. You would just disgurd the line from the 4. The question states you don't have to use this.

    Sent in by Matthew Dakin
    24 The border between Canada and the United States consists mainly of the 49th Parallel. If a Canadian airliner were to crash exactly on the parallel, in which country would the survivors be buried? (If you think about this for more than five seconds you have been taken in!)

    survivors wouldn't be buried... 
    25 What is the frequently used English word containing these letters, just like this: OOKKEE

    "bookkeeper"

    Sent in byRichard Givens
    26 A woman had triplets in July and twins in August - in the same year. How could that be possible?

    She had quintriplets (5), three were born before midnight on July 31 and two were born after midnight on August 1st.

    Alternatives:

    The woman may have given birth to three children in July, one needing to go into intenisve care for neonatal care after birth defects, dieing in August, leaving the mother with twins. Graphic I know, but happens frequently

    Answer posted by Melanie Watt
    27 Generally speaking, birds lay their eggs in nests up in trees or down at ground level. Where do peacocks lay theirs?

    Peacocks do not lay eggs, Peahens do.
    28 In the Records Office in London there are numerous documents headed "Proclamations of His Majesty King George I" published shortly after he came to the throne.’ That couldn’t be so. Why not?

    "If the documents were published just after his coronation, he would not be known as King George I.  He would not be called that until after the coronation of King George II."

    Sent in by Robert Gowland)
    29 A youth said: ‘The day before yesterday I was fourteen. Next year I’ll be seventeen.’ On what day was he speaking and when was his birthday? (No this has nothing to do with Leap Year)

    I THINK this is right. . . This day is the day after his fifteenth birthday, and also January 1.  His birthday is Dec. 31.

    Sent in by Renai McLean)
    30 Continue the sequence:

    192
    021
    222
    324
    252
    627
    2….?

    282, 930, 312, 1233... 

    Every second line is in sequence, 
    192, 222, 252, 282 (+30) 
    and then 021, 324, 627 (+303) 

    Alternatives

    The sequence of numbers is 282, 930, 313, 233, 343...  Take the numbers 19, 20, 21, 22, 23, 24, 25, 26, 27 which are in groups of 2 digits and move them into groups of 3 digits. 

    19 2 <-- twenty is split 
    0 21 
    22 2 <-- twenty-three is split 
    3 24 
    25 2 <-- twenty-six is split 
    6 27

    Sent in by Robert Gowland

    the next few could possibly be
    192
    021
    222
    324
    252
    627
    2...82
    920
    212
    223
    242
    526
    272

    if you look at the pattern of the numbers you see that we start with 192 then 021 then 222. looking in a diagonal direction going down and left we see a pattern emerging. 1, 90, 222, 123, 222, 456, 222, 789, 222, 012, 222, 345, 222. the sequence continues the pattern every second time.

    Alternative by Adam Brooke
    31 How to get the better of someone who thinks he knows everything about cricket! Ask him how many counties there are in the County Championship.

    The County Championship is the cornerstone of County Cricket and the most prestigious competition in which the 18 first-class counties take part.

     

    Inaugurated in 1890, the first official Championship was contested between just 8 counties: Gloucestershire, Kent, Lancashire, Middlesex, Nottinghamshire, Surrey, Sussex and Yorkshire, the first championship going to Surrey. Somerset was admitted the following season, followed by Derbyshire, Essex, Hampshire, Leicestershire and Warwickshire in 1895. Worcestershire was admitted in 1899, Northamptonshire in 1905 and Glamorgan - the current champions - in 1921. Durham, the newcomers, were admitted in 1992.

     

    Radical changes are planned for the new millenium. In a move to introduce a greater element of competition into the game, the 18 first-class counties will be split into two divisions of nine teams each, based on this season's performance in the championship.

    (Source Essex County Cricket Club http://www.essexcricket.org.uk/) 

    Alternative: a bit of lateral thinking

    'How many counties are there in the County Championship?' Only one 'county'

    Answer posted by Melanie Watt
    32 A silly one! There is a drain-pipe lying in the road. It is fifteen feet long. A squirrel pokes its head in at one end and then runs around and pokes its head in at the other end. If this takes six seconds and it doubles in speed each trip, how many trips will it have to make before it is poking its head into each end of the drainpipe at the same time?

    Actually it's not as silly as it sounds (well maybe it is) but in the world of mathematics and physics (to which the real world is only a close approximation) this puzzle is actually possible and I remember answering similar questions in my first year of phyiscs at university. If the question is actually taken literally the squirrel would be looking at himself after its 30th trip at which point it will be travelling at 408021893.12m/s (if I've done my maths correctly). It is during the squirrel's 30th trip that it has reached the speed of light and time would quite literally have stood still. By the time it reached the end of the pipe the sqirrel would have succeeded in travelling back in time and be looking at him or her self in the past. Or to think of it another way, the squirrel would have literally overtaken the light rays which are travelling through the pipe and if it stuck its head in the pipe after its 30th run the image hitting its eyes would be of itself sticking its head into the other end of the pipe. In theory it would then also be possible to take a photo of the event where the squirrel is sitting at both ends of the pipe at the same time. Of course it is quite debatable whether such time travel really is possible or whether the squirrel would have survived breaking the sound barrier or whether the squirrel could even find the end of the pipe while travelling at those speeds because any image that actually enters its eyes would be highly distorted (kind of like watching the starship enterprise engaging its warp drive) or whether the squirrel would not have escaped the earth's gravitational pull.

    Sent in by Jörg Ernst, UniSA Chaplain

    Question 32; The answer given to this question states that "in the world of mathematics and physics (to which the real world is only a close approximation) this puzzle is actually possible." I would like to point out that in the "world of physics" it is not possible for a body with finite mass to travel at the speed of light without having an infinite amount of energy. To travel at speeds greater than the speed of light would require an even greater amount of energy, which is just not possible. Therefore, the squirrel can not be going faster than the speed of light and so cannot be at both ends of the drain pipe at the same time.

    Sent in by D Judson, University of Brighton

    The question clearly states that the condition to be satisfied is that the squirrels head is poking into both ends of the pipe at the same time. This condition can not be satisfied even if it were possible to be travelling faster than the speed of light, because travelling faster that the speed of light does not stop or reverse time. In the case that the squirrel can travel faster than the speed of light, his head only appears to be poking into the other end of the drain pipe, but it isn't really there. Its the same as when we are looking at stars in the sky. The stars we see may not actually be there. The light which shows their destruction may not have reached us yet, but this doesn't affect whether or not at this instant the star exists.

    Sent in by Stuart Herring, London
    33 Which State returns a "Nil Births" every year

    Vatican State in Rome.
    34 Man has 7 neck vertebrae, how many does a giraffe have?

    7 !! - The giraffe's long neck has the same number of neck vertebrae (7) as most mammals, but they are greatly elongated.

    35 What predominant colour is a peacock’s egg?

    As with Question 27: Peacocks don't lay eggs
    36

     DONALD
    +GERALD
    =ROBERT

    If D = 5 What are the rest?

     526485
    +197485
    =723970

    Method/ Answer
    37 Circles or spiral?

    Spiral Illusion

    Circles - visual illusion

    Answer

    These are just lines with triangles on the end, not meeting others of their sort, therefore this diagram is neither a spiral nor concentric circles. 

    Sent in by Melanie Watt

    (Ed: true, but follow the line they make...)
    38

    You are in the army. You are standing at a gorge which is crossed by a rope bridge. It is pitch black and you only have one torch. You know the bridge is going to blow up in 17 mins and you have to get your 3 men and yourself across the bridge in 17 mins before the bridge blows.

    You take 1min to cross the bridge.
    X takes 2 mins to cross
    Y is overweight and takes 5 mins to cross
    Z is injured and takes 10 mins to cross.

    The rope bridge can only support the weight of two men at any one time. One of you must always return with the torch as it is impossible to cross the bridge if you can't see. Whoever crosses always takes the time of the slowest persons as you have to help them.

    How do you save all you team and do it??

    You and X go first (1 and 2 minute) - 2 minutes elapsed
    You run back - add 1 minute = 3 elapsed
    Y and Z go over - 10 minutes = 13 elapsed
    X goes back to pick up you - 2 minutes = 15 elapsed
    You and X go over again - 2 minutes = 17 elapsed.

    Sent in by Mike Bosch
    39 Using only three straight lines connect these nine dots, without lifting pen from paper or crossing over another line.

    Alternative

    The answer to Mindbender 39 seems a bit contrived, albeit interesting. I would submit that another 'solution' that is no more contrived is: Place the nine dots on a deflated spherical balloon with the center line of dots in line with the opening of the balloon. When the balloon is inflated, each of three rows of three dots will be on a great circle. It is then easy to select three segments of the great circles to solve the problem."

    Sent in by George Crofts

     
    40

    You want to send a valuable object to a friend. You have a box which is more than large enough to contain the object. You have several locks with keys. The box has a locking ring which is more than large enough to have a lock attached. But your friend does not have the key to any lock that you have. 

    Note that you cannot send a key in an unlocked box, since it might be copied. How do you do it?

    The person you are sending it to sends you their lock first. You then lock the box and send it to them. Because they have not sent the key nobody can intercept it and unlock the box.

    This is the basis to most computer encryption techniques on the web. When you encrypt something, you are doing so with that person's lock, they keep the key.

    Sent in by Tawanda Gurakumba

    The person could send the other person the box with a lock on and the friend puts another lock on the box. The friend then sends the box back to the first person who then removes their own lock and sends it back to their friend who can then take off their own lock and therefore open the box.

    Sent in by Jo Vincent

    If the box is more than large enough to contain the item, tie it to a short piece of cord which hangs over the side of the box, so the friend can open the lock with it. Unless one of the postmen is desperate to invade someone's privacy and open their mail, and even copy their key, he would definitely get sacked for cutting the cord, as he couldn't copy it with it on.

    Sent in by Melanie Watt

    Some combination locks are produced with emergency keyholes, just in case you forget or something. This justifies the "key". Send the box with such a combination lock and call your friend to tell him the combo.

    Sent in by Mango
    41 (Variation on question 23) 
    Remove one short line to make this correct:

      5 + 5 + 1 = 546

    Remove the / from the 4 to make the sum
    5 + 5 + 1 = 5 + 6

    Submitted by Louise Francis

    You could just remove one of the equals lines so that it is an unsolved equation

    Sent in by Melanie Watt
    42 A woman went to visit her bank manager and she took her young daughter with her. The bank manager said that the woman's daughter could stay with his secretary during the meeting. When the woman and her daughter left, the secretary turned to another secretary and said to her: 'That little girl was my daughter.' How could that be?

    The secretary was the girl's father.
    43 You have two traditional hourglass type egg timers. One takes seven minutes for the sand to run through, the other takes 11 minutes. You want to boil an ostrich egg for exactly 15 minutes. How do you do it? and how soon after the start of the whole process will the egg be ready?

    Start both timers together. When the 7 minute timer finishes, turn it over immediately. It will run for 4 minutes before the 11 minute timer finishes. Turn the 7 minute timer over again at that point and it will measure a further 4 minutes : 15 minutes in total.

    Alternative

    "assuming that the water is already boiling start by turning over both timers when the 7min timer runs out drop the egg in the water there will be 4 min left on the 11 min timer when the 11min timer runs out flip it for the remaining 11 min (11min+4min=15min) add the 7 min from the original timer you get 22min (or since you used the 11min timer twice)"

    Submitted by Linda Ostlie
    44

    Some silly questions for you, but you need to know a bit about physics to work these out.

    a) Mad Professor Zweistein has managed to build a car that has an unlimited to speed and incredible breaks that allow it to stop instantly. He only has one problem, the car is seven metres long and his garage can only accomodate a six metre car. How fast does Professor Zweistein need to drive the car so that it will fit into the garage and when does he need to apply the breaks?

    b) During his attempt to get his car into the garage, Professor Zweistein is caught by a red light camera for driving through an intersection while the light was red. In court Zweistein defended himself by saying that at the speed he was travelling the red light from the traffic light actually looked green (due to the doppler effect). Being a physics buff himself, the judge decided to take Professor Zweistein at his word. If the standard rate is $1 per km above the speed limit of 60 km/h, how much was the speeding fine issued by the judge to Professor Zweistein?

    a) This question is about relativistic length contraction. As the velocity of the vehicle increases, its apparent length, as viewed from a stationary position contracts. The amount of contraction is calculated using L' = sqrt[1-((v*v)/(c*c)]*L where L' is the contracted length, v is the velocity of the vehicle , c is the speed of light and L is the original, uncontracted, length of the vehicle. As the vehicles stationary length is 7m and it has to contract to 6m to fit inside the garage, the velocity required can be calculated as

    6 = sqrt[1-(v*v)/(c*c)]*7 which when rearranged gives sqrt{[1-(36/49)]*c*c} = v = 154523626 m/s. Now

    1 m/s = 2.2369 miles per hour so the car would have to be doing 345653900 miles per hour to give a length to contraction of 1m, as viewed from the stationary garage.

    b) The second part of the question asks when the brakes need to be applied. Once the brakes are applied, the vehicle is no longer travelling 345653900 miles per hour, relative to the stationary garage, its apparant length will return to the original 7m and so it will no longer fit in the garage. Therefore he should apply the brakes before he hits the back wall of the garage, but he will still not be able to fit the car inside!

    Sent in by D Judson, University of Brighton

    b) none- the judge took him at his word and didn't fine him.

    Submittedby Dawn (m y s t i c a l   .  d a w n)

    On question 44 about the mad Professor Zweistein, there are two parts. The first part involves two questions and a slightly complicated answer. However, assuming the first part was answered correctly, one can then answer the second part. Part B states that the Professor is caught on video tape running a red light. He is then taken to court for this offense. However, upon his hearing he defends himself by stating that at that speed the red light actually looked green. Well since the Judge is himself a physics buff, he realizes that the Professor is right. However, he then decides to give the professor a speeding ticket. The last Sentence of part B is "If the standard rate is $1 per km above the speed limit of 60 km/h, how much was the speeding fine issued by the judge to Professor Zweistein?" If you will notice, the professor was brought in for running a red light but was issued a fine for speeding. Since we have the answer as to how fast he was traveling from part A, we can then determine how much his fine was. The answer in part A states that the Professor was traveling at 154523626 m/s. Using a simple conversion of 1m/s = 3.6km/h we can deduce that the professor was traveling at 556285053.6Km/h. However, since the fine is $1 above 60km/h then you merely have to subtract 60km/h leaving you with a fine of $556284993.6.

    Sent in by Michael Hutchins

    The answer to Mindbenders 44 is incomplete at best. The statement that the car can instantaneously stop is not well defined. The reason is that instantaneous, or the phrase “at the same time” is dependent on the frame of reference you are in.

    From the frame of reference of the garage, the car back end of the car enters the garage at the same moment that the front end touches the back wall. If the car stops instantaneously in this frame of reference, that is every point in the car stops at this point in time in the garage frame of reference, then an extremely compressed car stops and is inside the garage.

    From the driver’s point of view the garage is compressed, but the front of the car touches the back of the garage long before the back of the car clears the door. If the car stops instantaneously in this frame of reference then the car is its normal size, but is never completely inside the garage.

    Now, if the car stops instantaneously in the garage frame of reference at the moment the front of the car touches the back of the wall, what is it like from the driver’s point of view. He sees the front of the car stop just as it touches the wall, but all points behind the front keep moving. Points further back stop at progressively later times. Since the front has stopped and the back is still moving, the car is being compressed. The back stops just as it sneaks inside the door, and a highly compact car is left.

    If the car stops instantaneously at the time the front touches the back wall from the driver’s point of view, what happens in the garage frame? Here the back stops first, long before the front reaches the back wall of the garage. Points further forward stop at progressively later times until the front stops just as it reaches the back of the garage. Because the front is now moving with the back stopped, the car is stretched from its apparent compressed form until it is its full length again.

    The key point is that two events that take place at the same time in one frame of reference may take place at different times in another frame. This is almost always forgotten in problems like this.

    Lee Loveridge, PhD
    45 You are trapped in the middle of a frozen lake that is so smooth that there is absolutely no friction so there is no way you can grip the ice. There is also no wind to propel you along. The only thing you have on you is a mobile phone, but unfortunately it has no reception so you can't call anyone for help. How do you get off the ice before you freeze to death?

    Quite simple really, throw away the mobile phone and while it glides off in one direction, the kick from the throw will propel you in the opposite direction (while the kick from a throw is not quite as large as the kick from firing a gun, it is still effective enough). Since the ice is frictionless you won't stop until you reach the shore. Then you can always walk around or take a run up and slide back across the lake to collect your phone.
    46 A butcher is 5' 10".  What does he weigh?

    Meat!

    47 There are 2 fathers and 2 sons sitting round a table. How many people are there?

    3 (a grandfather, who is a father, his son, who is a son and a father, and the grandfathers grandson, who is a son.)

    2 (Both sons sitting at the table are themselves fathers)

    Alternatives

    actually 2... every man is someones son... therefore if there are 3 men there were actually 3 sons.

    Sent in by William Volterman

    It could also be four- A father and his son, and a different father and his son [the two fathers not being related].

    Sent in by Kaitlyn
    48 Which English place name (also the name of a London tube station) contains 6 consecutive constantans?

    Kni(GHTSBR)idge
    49 What is?

    YYURYYUBICURYY4ME

    "Too wise you are too wise you be I see you are too wise for me."
    50 How many triangles?

    92 triangles

    David Yeck SWAP YFC/ Campus Life
    51 Every other day, a cyclist rides a bicycle over the border between the border of the US and Mexico. a policeman always checks his satchel, but it holds nothing but a water bottle. Yet, he is smuggling something between the two countries. What is it?

    Bicycles!
    52 There is a man who goes home one day, to see about answering his e-mail, when he sees Myrtle lying on the floor, dead. There is broken glass, and a large quantity of water on the floor. What happened?

    The broken glass is the fish bowl and Myrtle is a fish.
    53 Two men were found in a cabin in a hillside, dead. What happened? (Believe me, there is an answer to this riddle.)

    The clue is in the word 'in', Both men were killed in an avalanche that buried the cabin. Otherwise it should be 'Two men were found in a cabin on a hillside"

    "Alternate answer to # 53
    An airplane crashed into the hillside. The two men were the pilots in the cabin of the airplane."

    Sent in Trevor Pugh
    54 Can you complete the following common phrases
    e.g. "7 C of the R" = 7 Colours of the Rainbow 4 = G in A C C (C D)

    25 = S of F

    18 - Y R (C T - B D)

    3 = L in a H

    1 = F H H

    7 = S R of F N

    18 = W A B

    1 = S in the K of G M

    4 = G in A C C (C D)  # 4 Ghosts in a Christmas Carol (Charles Dickens)
    25 = S of F # 25 = square of five
    18 - Y R (C T - B D) # yellow roses?
    3 = L in a H # 3 lines in a haiku
    1 = F H H # 1 = fair high humidity
    7 = S R of F N # 7 = square root of 49
    18 = W A B # 18 = with a bullet
    1 = S in the K of G M #  1 sonata in the key of G Major

    I got this from a website:
    http://www.millenniumschools.co.uk/pub/essex/ourladyofransom/ai.html?1084197580

    Sent in by Laura Krzyston
    55 There is a man, who goes down into a room every day to check on his frozen meat, to make sure it doesn't thaw. One day, however, he is killed inside the room. No one else entered the room (aside from himself), and there is a trace of moisture on the floor. The authorities are baffled. Two questions: What kind of room was it, and, what killed him? (Note, he did not commit suicide.)

    The room is a freezer. An icicle or block of ice in the freezer fell on him and killed him. The water is all that remains of it after his remaining body heat melted it. Actually its more likely an icicle pierced him when it fell and then melted from his body heat. As unless the block of ice or icicle was next to him after he fell it would not melt.

    Alternate

    As it is a freezer room, their is frost on the floor, and, after eating some of the frozen, uncooked meat, the man died of food poisening and fell onto the floor, melting some of the frost with his body heat.

    Sent in Melanie Watt
    56 I was going over to visit my friend, Alfred, when I found him dead at his desk. There was a tape recorder on his desk. I pressed 'play' on the device, and found he was saying,"...A man just telephoned he was going to come over in 1 minute to kill me. I have no alternative, but to submit..." Suddenly, on the tape, there is a shot and a thud. However, I knew that the person who made the recording was not Alfred, but the killer! How did I know? (Use logic, please.)

    "The answer is that the tape player stopped after the thud, hence someone must have switched it off, and a dead man could not do this."

    Sent in by Rick Geatrell

    [Ed: but the statement does not say the tape had stopped after the 'thud' this is only a presumption... what would be the answer if the tape had been voice activated with auto stop or had just kept on running?]

    "I have reviewed my answer, and would now say that there is another answer. When he started the tape player, he heard his friend immediately, which means the tape player must have been rewound to the beginning, which must have been done by the murderer."

    ... or it could just be that being his friend you recognise it as not being his voice. btw: Why is Alfred talking to a tape recorder. Why was he not phoning the police?

    The person knew it was not alfred because HE was the killer. He called outside the office... threatened to kill him on the phone walked in and shot him. Then played the message after.

    Sent in by William Volterman
    57 What is black when you buy it, red when you use it, and grey when you throw it away?

    Coal
    58 An electric train is heading north at 60 mph. If the wind is blowing west at 30 mph, what direction is the smoke blowing?

    What smoke? Electric! Duh
    59 Divide 500 in half. How many times do you divide the dividend(?) before it reaches 0?

    The dividend is 500, if it is divided by 2, the quotient will be 250 but the dividend is still 500. If the quotient is then used as a new dividend and divided by 2 this can be repeated two times before the quotient becomes a fraction and as a fraction divided by 2 will always give another fraction, the answer is the dividend will never be exactly 0.

    Sent in by D Judson, University of Brighton
    60 What number is actually possible to divide in half to create (key word!) zero?

    i think the answer to question is "8", if you chop the "8" in half you get two zeros...

    Submitted by Paul Whittingham

    The answer to number 60 in the riddle section is "zero."  If you divide zero in half you get zero.

    Submitted by Rhonda Kilfoyle

    "8"

    Sent in by Alfred Jones
    61 Three brothers shopping for a TV walk past a shop and see a TV on sale for £30!. Bargain they think only £10 each as they always share the cost equally. So in they go to buy the TV, when they get to the assistant to purchase the TV. He informs them that they are the 1000 customer of the day and qualify for £5 discount!!!. so the brothers all hand the assistant £10 each, the assistant the goes to hand the brothers there £5 pound change, "oh we share things equally" says one brother, so they all agree to take back £1 each and tip the assistant the remaining £2.

    However if the brothers all handed over £10 each but received £1 discount, then they only spent £9 each...so in total they spent 3x9 = £27 and tipped the assistant £2, but 27+2 only equals 29??? were did the other £1 go!!!

    The question is misleading. The question states they paid £27 plus the £2 tip = £29. However in reality the tip is already included in the £27 they paid £25 [£30 - £5] + £2 tip = £27 [3 x £9]

    Sent in by Tini Garske
    62 2 sons and 2 fathers go fishing. They each catch one fish. The total number of fish they caught was 3 fish. How is this possible?

    It is a grandfather, a father, and a son. The father is a son to the grandfather, and a father to the son.
    63 A man wakes up in the middle of the night and wants a snack, so he goes downstairs, gets out a sandwich and a glass of milk from the refrigerator. He eats the sandwich and drinks the milk, then turns out the lights and goes to bed. In the morning, there are dead people on his lawn. Why?

    It was never said that he turned on the lights. The man lives in a lighthouse, so when he turned off the light, the people in the boats couldn't see and sailed into a cliff.

    64 What starts on four legs, then on two, then on three?

    A human! A baby crawls, a kid walks, and when you get old, you have a cane!
    65 AEEOEEIEUE... what is the next letter?

    "E"

    Sent in by Anne Gibbons
    66 A king is searching for a suitor for his daughter, so he collects the three smartest men in town. He sits them in a circle and tells them he is going to put a red mark or a white mark on each of their heads while their eyes are closed. He puts a red mark on all three and tells them to open their eyes. He then asks them if they see a red dot then they should raise their hand. They all raise their respective hands. He then says that if you know the color dot that is on your forehead, then stand up. After a few minutes one man stands and says the correct color. How does he know?

    If the man that stood up had a white dot on his head, then one of the other two men would have stood up immediately because they would have realized that they each had a red dot and both of them raised their hands. The key part to this mindbender is that they are all smart men, and that their was a pause before the man stood up.
    67 A man is standing in front of three light switches and then there is a shut door. He is only allowed to go through the door once and there he will see three light bulbs. By turning any light bulbs on or off the man must be able to know which light switch goes with which light bulb. E.g. He can turn two on and know which switch is for the unlit bulb but will remain uncertain about the other two.

    He turns one on, leaves it for ten minutes and then turn it off. Turn another on and walk in. One light bulb will be on, one off and one off and hot!
    68 A man is pushing his car across London. He eventually arrives outside a hotel in Park Lane and there discovers he has become bankrupt. How has this happened?

    He is playing Monopoly.