Who owns the fish?

Jessica B · 2005-06-25 00:42:01

I think the "Who owns the fish?" puzzle is great and really gets your mind working. We were set it in our maths class, and my partner and I completed it in 10 minutes! We also tried the pool balls problem but failed to work it out successfully. I think the whole site is really good - well done. Does anyone agree with me that logic puzzles are great fun? :-)

MathsIsFun · 2005-06-25 01:05:19

ME ! I love puzzles - I am not really good at them, but I like keeping my brain challenged.

Mr T · 2005-06-28 06:40:03

oh yes...they rock my world.

Zach · 2005-06-28 06:43:04

Spam rocks your world, I bet.

Mr T · 2005-06-28 06:58:40

i am sensing a theme from Zach's posts today

ezaspi · 2005-08-06 15:12:59

I heard that that "Who owns the fish?" puzzle was attributed to Einstein. Example: http://www.coudal.com/thefish.php. Is there any truth to that?

MathsIsFun · 2005-08-06 20:21:08

Indeed! It is often called "Einstein's Puzzle", and it is said he invented it as a boy.

In his original puzzle he does not mention the "Walleye Pike" that is on the coudal.com version ... they probably added that to get around the "nobody said anyone owned a fish" argument.

In our version of who owns the fish, you are expected to use your powers of logic to solve for the missing pet, which is assumed to be a fish, cause that is the title of the puzzle.

Jai Ganesh · 2005-08-07 16:56:20

If you all are interested in logical puzzles, here's one:-

A Captain has three smart soldiers under him. The three soldiers are informed that their intelligence is being tested and that the captain has three blue and two red caps. They are made to stand in ascending order of their heights. They are blindfolded and the captain puts a cap, chosen at random, on the heads of the three soldiers. The blindfold is then removed. The captain asks the third soldier whats the color of the cap on his head. The third soldier sees the color of the cap on the heads of the first two soldiers, but he says he is unable to tell the color of the cap on his head.
The Captain asks the same question to the second solider. The second solider takes into consideration the third soldier's reply and the color of the cap on the first soldier, which he is able to see. But, he too is unable to tell the color of the cap on his head.
The Captain then asks the same question to the first soldier. The first soldier has only the replies of the third and second soldiers to draw any conclusion. But he tells the color of the cap on his head. He gives the right answer.

What's the color of the cap on the first soldier's head and how did he answer correctly?

Last edited by Jai Ganesh (2005-08-07 16:57:58)

tt · 2005-08-08 13:29:50

Let 1,2,3 be the 1st, 2nd, 3rd soldier.
Case 1: R R B (1 and 2 wearing red cap and 3 wearing blue cap)
3 would have found out that he was wearing blue cap. But he couldnt tell so this is not correct order .
Case 2: R ? ?
2 would have known that he was wearing blue cap because if he was wearing red cap (case 1) then 3 figured out answer already.
But 2 couldnt answer so 1 must be not wearing red cap.
Case 3: B ? ?
2,3 wouldnt have enough facts to figure out the color of their caps.

1 considers case 1 and case 2 then he figures his cap is blue.

Last edited by tt (2005-08-08 13:38:24)

Jai Ganesh · 2005-08-08 16:28:39

Well done, tt! You got it right!

ryos · 2005-08-16 16:06:10

As an aside, did Einstein really think that 98% of the world would be unable to solve the puzzle? If you weren't allowed to use a paper and pencil (I used an excel spreadsheet ) it would be almost impossible, but with paper it's not very hard at all.

mathsyperson · 2005-08-16 20:15:36

It's probably something to do with the 'nobody owns a fish' argument. I think that was Einstein's answer and he thought that 98% of people would assume there was a fish.