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4 replies to this topic

### #1 abotaweeela

abotaweeela

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Posted 16 February 2008 - 01:33 AM

we have five hats 3 red and 2 yellow and we have three students in a line (all of them konew the number and color of the hats). the firist one can see the second and the third,and the second one can see the thrid one, and the third one can't see any one, then the teacher put one hat on the head of each student. the teacher asked the students, what is your hat color?
first one:I dont know
second one:I dont know
the third one:it is red.
how the third one knew his hat color?

Edited by abotaweeela, 16 February 2008 - 01:41 AM.

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### #2 PolishNorbi

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Posted 16 February 2008 - 01:38 AM

we have five hats 3 red and 2 yellow and we have three students in a line (all of them konew the number and color of the hats). the firist one can see the second and the third,and the second one can see the thrid one, and the third one can't see any one, then the teacher put one hat on the head of each student. the teacher asked the students, what is your hat color?
first one:I dont know
second one:I dont know
the third one:it is red.
Explan that.

Spoiler for Solution

Edited by PolishNorbi, 16 February 2008 - 01:46 AM.

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Posted 16 February 2008 - 01:49 AM

easy, the third knows he and the second dont both have yellow because the first didnt answer, the second knows this to but since he didnt answer he must have seen that the third had red. the third knows this so he knows he must have red.

( i hope i got the first, second and thirds right, it was confusing)

Edited by TwoaDay, 16 February 2008 - 01:50 AM.

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### #4 bonanova

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Posted 16 February 2008 - 01:57 AM

Spoiler for solution

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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

### #5 rookie1ja

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Posted 16 February 2008 - 02:51 AM

if you like this type, be sure to check the following:
Masters of Logic Puzzles I. (dots)
Masters of Logic Puzzles II. (hats)
Masters of Logic Puzzles III. (stamps)
Christmas Tree

looking forward to new puzzles

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