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Lateral Thinking - Try these when ur half asleep!

  • 05-03-2003 6:24pm
    #1
    Registered Users, Registered Users 2 Posts: 9,472 ✭✭✭


    1. There are 3 light switches outside a room. Inside that room is a light which is connected to only ONE of the switches outside. You must figure out which switch is connected to the lightbulb and you are only allowed go into the room and check once.

    HINT 4 DRUNK PEOPLE - The lite bulb heats up when switched on

    2. You have a 3litre container and a 5litre container aswell as a plentiful supply of water VIA a tap. You must fill the 5litre container so that it has exactly 4 litres in it! (No guessing), How do you go about doing it!

    3. There are 12 coins on a table, one is lighter or heavier than the rest, you have a balance scales which you may only use 3 times. You must single out the lighter or heavier coin... How?

    HINT 4 DRUNK PEOPLE - Try find the weight of 1 coin

    4. A Fruit Grower fills 3 boxes. 1 with apples, 1 with pears and the other with a mixture of both. Then an employee comes along and accidently labels ALL the boxes incorrectly and seals the boxes. The Grower comes back (knowing the labels are wrong) and opens only 1 box and takes something out, now he knows exactly what fruits are in all of the other boxes, how?

    HINT 4 DRUNK PEOPLE - Any hint would give it away!

    Post answers in the form of replies... It'll be good to see how smart the Boards community is!


Comments

  • Moderators, Arts Moderators Posts: 35,917 Mod ✭✭✭✭pickarooney


    1. Turn the first switch on, and leave it for a minute. Turn it off.
    turn the second switch on and walk into the room. If the light is on, it's the second switch. If the light is off, but the bulb is hot, it was the first switch. If the bulb is off and cold, it's the third switch.

    I needed the hint.

    2. Fill the 3-litre container and pour it into the 5-litre. Fill the 3-litre again, and carefully pour it into the 5-litre until it can fit no more. Empty the 5-litre. you now have 1 litre in the small container, which you pour into the big one. Refill the 3-litre and pour it into the 5-litre to give you 4 litres.

    3. No idea (yet).

    4. By labelling hte boxes incorrectly, does this mean that one of the boxes is marked Apples, one is marked pears and one is marked Mixed?


  • Registered Users, Registered Users 2 Posts: 6,315 ✭✭✭ballooba


    3)put 12 coins on the scales. measure and divide by twelve, thus getting average weight of the twelve....(don't know the rest)

    4) the one he opens contains the right thing so the other two labels have to be swapped.


  • Registered Users, Registered Users 2 Posts: 1,997 ✭✭✭The_Bullman


    3) put 3 coins on each side of the scales. Whichever is heavier will go down. so take two of these 3 coins and put 1 on each side of the scales. If one side goes down then it is the heavy one. If it is even then the remaining coin is the heavy one


  • Registered Users, Registered Users 2 Posts: 2,188 ✭✭✭Serbian


    Originally posted by The_Bullman
    3) put 3 coins on each side of the scales. Whichever is heavier will go down. so take two of these 3 coins and put 1 on each side of the scales. If one side goes down then it is the heavy one. If it is even then the remaining coin is the heavy one

    Not quite right, I made the same mistake myself actually by assuming that the odd coin out is heavier than the rest. If it was heavier you'd just split the coins into 2 groups of 6, whichever group was heavier, split that in to two groups of 3, then take the group that is heavier. Put two of the coins into to either side of the scales. Either one of the coins will be heavier than the other, or they will be the same weight (indicating that the 3rd coin is the special one)

    However, the question is: 3. There are 12 coins on a table, one is lighter or heavier than the rest... So it could be lighter too. I'm not exactly sure how you could tell the difference in that case...


  • Registered Users, Registered Users 2 Posts: 9,472 ✭✭✭AdMMM


    Well done... between you, you have all done very well, answering the conundrums, however, I can't get the one with the coins... and either can you it seems, so lets all pull together as a team!


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  • Registered Users, Registered Users 2 Posts: 9,472 ✭✭✭AdMMM


    About the coin one.

    I'm stuck... I've put many possible solutions through my mind, but dismissed them when I realised they led only to a Cul De Sac...

    This is one I'm working on now:

    Pick any two coins from the twelve and weigh them. If they balance that means that they are both the same weight, therefore multiply by 6 to get the weight of what all 12 should add up to. Then put all 12 onto the scales and put a counter weight on the other balance until they balance. If the total it add's up to is less than what you originally multiplied by then the odd coin is less, if the weight needed was more than what you multiplied by then the odd coin is heavier. Now... Oh crap! Now I'm stuck... If only you were alowed 4 weighs!

    God dangit!


  • Closed Accounts Posts: 1,669 ✭✭✭DMT


    Originally posted by pickarooney
    2. Fill the 3-litre container and pour it into the 5-litre. Fill the 3-litre again, and carefully pour it into the 5-litre until it can fit no more. Empty the 5-litre. you now have 1 litre in the small container, which you pour into the big one. Refill the 3-litre and pour it into the 5-litre to give you 4 litres.

    An alternative:

    Fill the 5 litre, pour into the 3-litre till it can fit no more. You now have 2 litres in the 5 litre bottle.

    Empty the 3-litre bottle and pour the 2-litres from the 5-litre bottle into it. Now fill the 5-litre bottle and fill the 3-litre bottle to the brim.

    Behold, you now have:
    4 mighty litres in the incredible 5-litre "bottle"
    .


  • Registered Users, Registered Users 2 Posts: 594 ✭✭✭eden_my_ass


    Maybe I'm missing something....


    4) the one he opens contains the right thing so the other two labels have to be swapped. - ballooba

    but....
    accidently labels ALL the boxes incorrectly - [JcCM]Murderer

    so that can't be right, surely? . However if the boxes are labelled A, P and M, and say he opens A and it contains M, then if they were all labelled wrong, P must contain A and M must contain P . Simple deduction (I think?).


  • Closed Accounts Posts: 1,669 ✭✭✭DMT


    Originally posted by ballooba
    3) put 12 coins on the scales. measure and divide by twelve, thus getting average weight of the twelve....(don't know the rest)

    That's wrong. It's a balance scales, so there is no way to *measure* the weight of the coins.

    4) the one he opens contains the right thing so the other two labels have to be swapped.

    That can't work either, because *ALL* the boxes have been marked incorrectly.


  • Registered Users, Registered Users 2 Posts: 594 ✭✭✭eden_my_ass


    4) the one he opens contains the right thing so the other two labels have to be swapped.

    That can't work either, because *ALL* the boxes have been marked incorrectly.

    Didn't I just say that??


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  • Closed Accounts Posts: 1,669 ✭✭✭DMT


    If there were only 3 coins in total, it would take two uses of the scales (worst case scenario) to determine which coin is the light/heavy one.

    Therefore, it would be necessary to eliminate 9 of the coins with one use of the scales and I can't see how that's possible....

    [edit]
    Originally posted by eden_my_ass
    Didn't I just say that??
    Didn't reload the page before posting...
    [/edit]


  • Registered Users, Registered Users 2 Posts: 594 ✭✭✭eden_my_ass


    Fair enough so....nice to see someone else spotted it though :D


  • Closed Accounts Posts: 1,669 ✭✭✭DMT


    Gave up and found the solution with a bit of googling.

    (Spoilering it for those you haven't given up yet)
    From: http://www.easyspooler.com/teaser3.html
    1st turn

    Divide the 12 coins into 3 stacks of 4 coins each. Place the 1st stack on the left side of the scales and the 2nd stack on the right side. If the scales don't balance, note which side is up and which side is down.

    2nd turn

    If the scales balanced on the 1st turn:

    The odd coin must be in the 3rd stack. Remove the top 3 coins from one side of the scales and set them aside, then replace them with the top 3 coins from the 3rd stack. If the scales don't balance, note which side is up and which side is down.

    If the scales didn't balance on the 1st turn:

    The odd coin is on the scales but you cannot yet determine if it is heavy or light or which side its on. Remove the top 3 coins from the left side of the scales and set them aside. Take the top 3 coins from the right side and place them on top of the coin on the left side, then take the top 3 coins from the 3rd stack and place them on top of the coin on the right side. If the scales don't balance, note which side is up and which side is down.

    3rd turn

    If the scales balanced on the 2nd turn:

    If the scales balanced on both the 1st and the 2nd turn, the odd coin is the bottom coin from the 3rd stack. Weigh it against any of the other normal coins to determine if its heavy or light. If the scales didn't balance on the first turn, then the odd coin is one of the 3 that you removed from the left side in the 2nd turn. You know if its heavy or light by remembering if the left side was up or down. Determine the odd coin by weighing 2 of the 3 against each other. If they balance, then it's the other one.

    If the scales didn't balance on the 2nd turn:


    If the scales balanced on the 1st turn but now they do not, the odd coin is one of the 3 that you just put on. That side of the scales will be down if its heavy up if its light. Determine the odd coin by weighing 2 of the 3 against each other. If they balance, then it's the other one.

    If the scales are in the same position as they were on the 1st turn, then the odd coin is the bottom coin on either the left or the right side of the scales and all the other coins are normal. Weigh one of the bottom coins against any one of the normal coins. If it raises the scales, its light. If it drops, its heavy. If it balances, it's the other one and you know if its heavy or light by remembering if the side of the scales you got it from was up or down.

    If the scales flip-flopped, then the odd coin is one of the top 3 coins on the left side of the scales. If the left side of the scales is up, its light. If it is down, its heavy. Determine the odd coin by weighting 2 of the 3 against each other. If they balance, then it's the other one.


  • Closed Accounts Posts: 2,590 ✭✭✭lordsippa


    Great. Now my head hurts. I hate you all. <stomps off to bed>


  • Registered Users, Registered Users 2 Posts: 9,472 ✭✭✭AdMMM


    That coin one was really peeing me off!


  • Registered Users, Registered Users 2 Posts: 14,181 ✭✭✭✭Jim


    any more??


  • Closed Accounts Posts: 5,093 ✭✭✭woosaysdan


    they are really annoying!!! if a red house is made out of red bricks, a blue house out of blue bricks, a black house out of black bricks, a purple house out of purple bricks, a yellow house out of yellow bricks, a white house out of white bricks whats a green house made of???

    you were driving a bus in dublin and there is 10 people on board, at the first stop 15 ppls get on and 3 get off, at the second stop 11 get on and 5 get off, and the next stop 22 get on and 3 get off, and the next stop 14 get on and 4 get off!!! ok got all that? what was the mane of the bus driver???

    marys father has 3 daughters nina and marie what is the mane of the third?


  • Registered Users, Registered Users 2 Posts: 15,399 ✭✭✭✭Thanx 4 The Fish


    Glass

    Me

    Mary


  • Users Awaiting Email Confirmation Posts: 729 ✭✭✭popinfresh


    if you know whether the coin is lighter or heavier then it's possible. Put 6 on both sides. the the lighter side contains the light coin. then divide that into 2x3 do the same as before. and you narrow it down to three. then you get two of the three remaining coins and weigh them, if one is lesser, then that's the coin ur looking for, but if they balance you know it's the one you didn't put on. Now lets say you have 20 coins one of them is lighter than the rest and again you have 3 shots on the scales. (yes it is possible :) and made up the solution myself)


  • Registered Users, Registered Users 2 Posts: 9,472 ✭✭✭AdMMM


    Originally posted by popinfresh
    if you know whether the coin is lighter or heavier then it's possible. Put 6 on both sides. the the lighter side contains the light coin. then divide that into 2x3 do the same as before. and you narrow it down to three. then you get two of the three remaining coins and weigh them, if one is lesser, then that's the coin ur looking for, but if they balance you know it's the one you didn't put on. Now lets say you have 20 coins one of them is lighter than the rest and again you have 3 shots on the scales. (yes it is possible :) and made up the solution myself)

    Yes but you dont know!

    I will post more of those tomorrow!


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  • Registered Users, Registered Users 2 Posts: 9,472 ✭✭✭AdMMM


    1.

    5 HOUSES


    1. There are 5 houses in 5 different colors, all in a row.

    2. In each house lives a different person with a different nationality.

    3. These 5 people drink a certain type of beverage, smoke a certain type of cigar, and keep a certain pet.

    4. No person has the same pet, smokes the same brand of cigar, or drinks the same beverage.

    The question is "Who owns the fish?"

    The Brit lives in the Red house.
    The Swede has a dog.
    The Dane drinks tea.
    The Green house is on the left of the White house.
    The Green house's owner drinks coffee.
    The person who smokes Pall Mall has a bird.
    The owner of the Yellow house smokes Dunhill.
    The man living in the center house drinks milk.
    The Norwegian lives in the first house.
    The man who smokes Blends lives next to the cat owner.
    The man who owns a horse lives next to the one who smokes Dunhill.
    The man who smokes BlueMaster drinks beer.
    The German smokes Prince.
    The Norwegian lives next to the Blue house.
    The man who smokes Blends has a neighbor who drinks water.


    2.

    The Census Taker


    A census taker approaches a house and asks the woman who answers the door,"How many children do you have, and what are their ages?"

    Woman: "I have three children, the product of their ages are 36, the sum of their ages are equal to the address of the house next door."

    The census taker walks next door, comes back and says, "I need more information."

    The woman replies, "I have to go, my oldest child is sleeping upstairs."

    Census taker: "Thank you, I have everything I need."

    Question: What are the ages of each of the three children?


    3.

    Sam Slug was found guilty of murder and sentenced to death. While waiting on death row, he escaped, got hold of a gun, and managed to board a plane. Just before departure, Sam hijacked the plane, and ordered all the passengers off. His next demand was for $500,000 in a heavy bag and a parachute. He then instructed the pilot to turn his radio off and fly at low altitude. When Sam saw the area he liked he strapped the parachute on and leapt from the plane. Unfortunately for Sam, in his excitement he forgot the money. When the pilot returned to the airport he reported to Detective Shadow that Sam Slug had made a successful escape but had left the money. Shadow immediately announced the case was closed. Why would Shadow not search for a convicted murderer?

    4.

    Mr. Dodgers and the children in the neighbourhood are raking leaves at Mr. Dodger's house. They have three piles of leaves in the back yard, and seven piles of leaves in the front yard. When Mr. Dodgers and the children put all the piles together, how many piles of leaves will they have?

    5.

    There are three men standing behind a curtain and you cannot see any of them. Each of the men have their faces painted. The color of their face can be either blue or green. Blue faced men always tell the truth and green faced men always lie. Each man must make a statement regarding the color of his face. The first man says something but you can't hear him. The second man says, "The first man said his face is blue. It is blue, and my face is blue, too." Then the third man says, "The first two men are lying, their faces are both green and mine is blue."

    Determine the color of each man's face.

    6.

    What is this:
    12S34A56F78E90T12E34Y56

    7.

    On a piece of paper, the numbers: 10 10 10 are written on it. With only one stroke of a pen, you must turn it into nine-fifty. How do you do it?

    8.

    The Dean wants to hire a fast thinking department head. She interviews three candidates at once and gives them a test. She has them close their eyes and she places a green mark on each of their foreheads. She tells them that she has placed either a green mark or a red mark on their foreheads. She tells them that when they open their eyes they are to raise their hand if they see a green mark on anyone’s forehead. They open their eyes and all three raise their hands. She then asks them to tell her what color the mark is on their own forehead, which they can’t see. One of the profs waits a while and then announces, "The mark on my forehead is green." What is the reasoning that led her or him to make this deduction?

    PLEASE NOTE THAT I ONLY KNOW THE ANSWERS TO A FEW OF THESE AND ONLY QUICKLY GOT THEM FROM A SITE


  • Moderators, Arts Moderators Posts: 35,917 Mod ✭✭✭✭pickarooney


    Some nice ones there :)

    I've done the houses one before, it's quite easy but takes time, so I'll not bother :D

    For the leaves, if they put them all together it makes one big pile.

    The 1st and 2nd men's faces are blue and the last one is green.
    (if what the third guy says is true, both others are lying, but also contradicting one another, which can't be, so he must be lying and the opposite of what he says is true. This tallies with what the second man says)

    No. 6 is SAFETY in numbers.

    For no. 7, draw a line through the second 1 to make a T and spell out "ten to ten", or 9.50.

    I think for the last one, the Dean has a green mark on her own forehead, which all three see. No, that doesn't work...
    If only one of them had a green mark, that person wouldn't see a green mark on anyone else's head. They all raise their hands, so this is not true. Therefore, at least two of them have to have a green mark. The prof(#3)who raises his hand sees that one of the others(#1) has a red mark, so knows that he himself must have a green mark, or the last prof (#2) wouldn't see any green marks and thus not raise his hand.
    This seems a bit unfair to the prof with the red mark, though, as he would only see two green marks and not be able to draw the same conclusion.

    EDIT : crap, just re-read it and they all have green marks. Okay, so #3 assumes that all three have an equal chance at the job, and are given the same information to work out the answer, therefore they all must have green marks.


  • Moderators, Arts Moderators Posts: 35,917 Mod ✭✭✭✭pickarooney


    For number 3, I'll go with the simple answer and say the plane was at too low an altitude for the parachute to open, though I don't like this answer.


  • Moderators, Arts Moderators Posts: 35,917 Mod ✭✭✭✭pickarooney


    Number 2 is just weird, and I think there's some info missing.
    However, her kids could be the following ages

    36, 1, 1 (rather unlikely for her to be fertile over such a long period, so rule that out)
    18, 2, 1
    12, 3, 1
    9, 4, 1
    9, 2, 2
    6, 6, 1 (she mentions an eldest child, so twin first-borns are out)
    6, 3, 2
    4, 3, 3

    If we knew whether she lived in an odd or even numbered house it might help. Or if we knew what the neighbour told him :)


  • Closed Accounts Posts: 2,256 ✭✭✭Molly


    Nationality Norwegian         Dane       Brit             German       Swede
    Colour      Yellow            Blue       Red              Green        White
    Drink       Water             Tea        Milk             Coffee       Beer
    Pet         Cat               Horse      Bird             [b]Fish[/b]         Dog
    Cigar       Dunhill           Blend      Pall Mall        Prince       Blue Master      
    
    


  • Registered Users, Registered Users 2 Posts: 4,839 ✭✭✭Hobart


    2 Men are fishing.

    When they are finished they meet up.

    "How many fish have you caught?" says one to the other.

    "Theres a strange thing, I have not caught the same amount as you but if you gave me 3 of your fish I would have twice as many as you. But if I gave you 2 of mine you would have 3 times as many as me!!"

    How many fish did each have?


  • Registered Users, Registered Users 2 Posts: 9,658 ✭✭✭irishgeo


    Originally posted by [JcCM]Murderer
    2. You have a 3litre container and a 5litre container aswell as a plentiful supply of water VIA a tap. You must fill the 5litre container so that it has exactly 4 litres in it! (No guessing), How do you go about doing it!


    Thats from Die Hard with a vengence.


  • Registered Users, Registered Users 2 Posts: 11,998 ✭✭✭✭Giblet


    Originally posted by Hobart
    2 Men are fishing.

    When they are finished they meet up.

    "How many fish have you caught?" says one to the other.

    "Theres a strange thing, I have not caught the same amount as you but if you gave me 3 of your fish I would have twice as many as you. But if I gave you 2 of mine you would have 3 times as many as me!!"

    How many fish did each have?
    First guy has 5, second has 7. If you took 3 from the second guy, he would have four, and the first guy would have 8, which means he would have twice what the second guy had. If you took 2 from the first guy, he would have 3, and the second guy would have 9, making him have three times the amount of the first guy


  • Closed Accounts Posts: 286 ✭✭Kev


    2. the census taker

    as the census taker needed more information after finding out the number of the house next door, and the fact that only two of the possible combinations of ages (1 6 6 and 2 2 9) sum to the same amount, it must be one of these combinations, as the woman says she has an eldest son it must be 2 2 9.

    8.

    as each of the men raised their hands they all know that there cant be 2 or more red dots, in the second round if someone could see a red dot he would know he had a green dot so would raise his hand, as nobody did raise their hand initailly there must be no red dot, so the smart guy knew he must have a green dot.


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  • Registered Users, Registered Users 2 Posts: 9,472 ✭✭✭AdMMM


    /bump


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