Need some more good brain teasers

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You have a 17 Litre Jug and a 9 Litre Jug, how do you make 5 Litres? - Pretty easy

In a "seven-eleven" (7-11) store, a customer selected four items to buy. The check-out clerk says that he multiplied the costs of the items and obtained exactly 7.11, the very name of the store! The customer calmly tells the clerk that the costs of the items should be added, not multiplied. The clerk then informs the customer that the correct total is also $7.11.

What are the exact costs of the 4 items?

This can be very hard if you don't spot the trick!

You have 12 marbles, one of them is either heavier or lighter than the rest. In three weighs on a balance scale, you must determine which is the odd marble. How do you do this? - This is pretty long to answer, you need a very methodical approach
 
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3 tourists walks in to a hotel and pays 30 quid all togather for 3 single rooms.(10quid a room)

the manager soon realizes that they should have only be paying 25 quid all togather as there was a offer going on.

so he gets the bell boy and gives him 5 quid to give to the 3 tourists.
the bell boy gets it in 5 one pound coins, so decides to keep 2 quid as tip and gives a quid each to the tourists..

so that means that the trourists spent 9 quid each as they all gave 10 quid and got back a quid.

3x9 equals 27
27 + 2 (the 2 quid the bell boy got as tip) equals 29 pounds..
and it should be 30 pounds all together ... where did he missing quid go?
 
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shimy182: You should be taking away 2 pounds from 27 and not adding it to get the total cost of £25 pounds :p

Each of them originally pay 10 each, so 30, they get 1 pound back, so they spend 9*3 = 27, and the bell boy TOOK 2 pounds, which would have otherwise gone back to the customers, so they would have spent less than £9 each and this is then timed by 3 .. long sentence ... so you should subtract the 2 quid from 27 and not add it, it doesn't make sense to do this.
 
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carvegio said:
shimy182: You should be taking away 2 pounds from 27 and not adding it to get the total cost of £25 pounds :p

Each of them originally pay 10 each, so 30, they get 1 pound back, so they spend 9*3 = 27, and the bell boy TOOK 2 pounds, which would have otherwise gone back to the customers, so they would have spent less than £9 each and this is then timed by 3 .. long sentence ... so you should subtract the 2 quid from 27 and not add it, it doesn't make sense to do this.

you spoilt it for the others...
 

~J~

~J~

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One of my old faves as a child...

What has 4 legs, has 2 legs, has 3, but the more legs it has, the weaker it be?
 

~J~

~J~

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100% correct, yes it is. Did a little project when I was 10 at my primary school and that was on the card on my paper-maché sphinx :D
 
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