The Student Room Group

Riddles guessing game!

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Guys! You're reading way too much into this! In answer to the coins, it's about how if you view it on the side it's appears to be a rectangle.
Only created this thread for a bit of fun!
Original post by kristen2
it's about how if you view it on the side it's appears to be a rectangle.


Yes we understand that but the truth is it does NOT appear to be a rectangle. There is no position you could view that stack of coins and see a perfect rectangle, not one single position. You can pretend it's a rectangle if you like, you can say "well it's near as damn it a rectangle" but the reality is that it isn't a rectangle and can never be one. Read prev posts for explanation why.
Original post by PilgrimOfTruth
@Otah007

Are you going to have another go at the coffee-milk conundrum?

Here's a clue, and a useful way to solve any problems such as this one. If a problem, in its asking, does not state specific volumes or measurements, then by definition, the solution must work for ANY volume or measurement. That being the case, you can use whatever volumes you wish, so use volumes that are useful. You can deduce the answer without any maths at all if you choose the right volume.


So if there's only a teaspoon of each, then you mix all the milk with the coffee, mix, and take out half of the 50% coffee 50% milk mix - so both have the same amount of each?
Original post by PilgrimOfTruth
Ok my contribution.

An oldie but goodie.

There is a cup of black coffee and a cup of white milk. Equal volumes and sizes.

You take a teaspoon of the coffee and put it in the milk and stir it up. Assume it is now a uniform solution.

You then take a teaspoon of the Milk-coffee solution and put that into the black coffee cup and stir it up.

Question

Which cup now has the most of its original liquid?

Does the coffee cup have more coffee in it than the milk cup has milk? or vice versa?

Guesses are not permitted here as there are clearly only 3 possibilities.

Make your guess and provide the proof.


By the same "holy logic of reality", you can't really know the answer because some of the volume was lost in transfer by the the teaspoon. Also, the liquid would have evaporated by some amount during this time, and again you won't be able to PRECISELY tell. :-)

Furthermore, cups can never have the exact same volume and size as another - no matter how deep you go into the measurements, man or machine cannot make two exactly identical cups.

Therefore, the answer is "we don't know".

:-) :-) :-) :-)
Original post by otah007
So if there's only a teaspoon of each, then you mix all the milk with the coffee, mix, and take out half of the 50% coffee 50% milk mix - so both have the same amount of each?


Bingo yes well done.

This is a technique to be remembered. I've seen some eloquent maths breakdowns of the puzzle usually using 10ths or 11ths which can prove the result, but by far the easiest way is just as you've done it.

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