School teacher has a bag of hats

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OK OK. Well Done Njorl.

I will post another that is correct for you all.

Sorry about this one.

The Bob (2004 ©)
 
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I remember in high school, there was a teacher who gave us broken brain teasers. He would give us a puzzle, and ask us to fix the puzzle so that it was solvable, but not trivial, then solve it. I wasn't very good at them then.

Strangely, working in the real world prepares you for this more than school. In school, they almost always give you problems with possible solutions. At work, it just isn't that way. In fact the first step is to explore if a problem can be solved. After 25 years, I can finally do broken brain teasers!

Njorl
 
Yes, Njorl's post 11 is the solution.

Also, this problem is a little too pacifist for my taste. A more exciting version is the primitive tribal village that is visited by a missionary.

According to custom, if a woman discovers her husband has been unfaithful, she must kill him at midnight that very same night. Naturally, considering the consequences, villagers make sure no woman finds out her husband is cheating on her. Meaning all the men are unfaithful with only the meagerest attempts to hide the fact and none of the wives ever find out THEIR husband is cheating. They only know the husbands of all the other wives are cheating.

A missionary comes to the village and is apalled to discover one of these affairs and to be strongly suspicious that there are several more. She immediately calls a meeting of the 60 married couples and informs them, "I'm seriously disappointed in you people. I know at least one husband has been unfaithful to his wife. It's a good thing I've come to put end to this behavior."

What will happen as a result of the missionary's comments?
 
Hey Bob, this is a nice one, but has been posted here before - with Hungarians instead of tribals, I think.

Those that haven't seen that thread may still work on this.

PS : I recommend starting each new puzzle in a new thread with an appropriate title, so it's easy to locate.
 
Well I reckon all of the husbands will think she is talking to them and not come home to face the wife. However lots do it so they all know who is and who isn't guilty.

I think that is the point.

The Bob (2004 ©)
 
(not trying to act stupid ) The white hats often reflects heat,while the black hat absorbs heat,if he was supposedly smart(like Njorl said),he would have taken the time when the teacher was asking the students to identify the hat on his head by feeling the heat,and since there isn't any calculations and a probability of 4/7 3/7,i can say that his hat was black,by then he would have noticed his head felt really hot.(again this is also an assumption)
 
idontthinkright said:
(not trying to act stupid ) The white hats often reflects heat,while the black hat absorbs heat,if he was supposedly smart(like Njorl said),he would have taken the time when the teacher was asking the students to identify the hat on his head by feeling the heat,and since there isn't any calculations and a probability of 4/7 3/7,i can say that his hat was black,by then he would have noticed his head felt really hot.(again this is also an assumption)

Indeed it is an assumption so for you I will say that they cannot feel their hats and so he cannot tell. The room is also 14 °C so in the (lets say) 20 minutes they are in there there is no way a change in temperature is noticeable. Plus unless the pupil knew the material of the hat and what a white hat was like to wear in those conditions so if he was wearing a black hat he would not know the different. :biggrin:

The Bob (2004 ©)