Japanese Elementary School Exam
One of my Japanese coworkers' son is enrolling in first grade at a private school here in Japan. He had to take an entrance exam which I found absolutely fascinating. One of the questions is below. He was given 3 minutes to answer it. We haven't done a puzzle in a long time, but please PM me your answer!
The basic gist of this problem is as follows:
There are four (a, b, c, d) students. Two have brown hair (X) and two have blonde hair (O). One student with brown hair is on one side of a wall (|) while the rest are on the other side in a line. Every person is facing the wall. (So the three people on the right are looking at the wall and can only see the people in front of them. The students are told that there are 2 people with brown hair and two people with blonde hair. Unfortunately, they do not know the color of their own hair. The students are not allowed to talk to each other and are not able to turn around. Which student (if any) can say what color hair they have?
To clarify:
Student a can see nobody.
Student b can see nobody.
Student c can only see b.
Student d can only see c and b.
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Sent you my PM. Its relatively simple when drawn out - assuming your description is correct and that each student can see all of the kids in front of him.
Its not unusual for kids to take a test here although that would be for a private school. We were going to do that for Ben but he was quite upset at the thought of losing all of his friends despite our assurances. I am sure he would have passed the exam and the school is one of the best. It would have really pushed him.
My wording wasn't very good. The wall between A and B can not be seen through. So the students can see everybody in front of them UP TO the wall. Nobody can see A.
Send you what I think the answer is. However, that is a very, very badly written question.
Heh, yea. That is my fault though.
I drew a picture to better illustrate the question.
Three wise men are told to stand in a straight line, one in front of the other. A hat is put on each of their heads. They are told that each of these hats was selected from a group of five hats: two black hats and three white hats. The first man, standing at the front of the line, can’t see either of the men behind him or their hats. The second man, in the middle, can see only the first man and his hat. The last man, at the rear, can see both other men and their hats.
None of the men can see the hat on his own head. They are asked to deduce its color. Some time goes by as the wise men ponder the puzzle in silence. Finally the first one, at the front of the line, makes an announcement: “My hat is white.”
He is correct. How did he come to this conclusion?
Because he knew the man in the middle lied on his application to be a "wise" man?
Dammit. I got confused on WW?. I got the full answer now.
Are any of the students allowed an Uzi?
Just asking
Yes.