Hmm... Here's a riddle...?

Question

A social studies teacher assigns a test. After the test was complete, he tells the students to trade tests with somebody taller than them so they can grade it.

If everybody in the class is a DIFFERENT height, and there are 30 students, how many trading possibilities are there possible?

No hints will be given. First correct answer gets 10 points.

fantasma · Accepted Answer

0

If the students can only give their paper to someone taller, then the tallest student has no one to give his paper to, so there are no trading possibilities that will work for all the students.

prettyprincess · Answer

29

janet · Answer

I think it is 15.

If there are 30 students, one of them is the tallest and one of them is the 2nd tallest.  So if the tallest goes with anyone other than the 2nd tallest, then the 2nd tallest will not have someone taller than him.  So, the tallest and 2nd tallest team up.  It goes on from there, with the 3rd tallest having to pair up with the 4th tallest, and so on.

This is assuming that it is okay for the tallest student and 2nd tallest student to trade tests.  The tallest student actually has no one taller than he is.

Valery S · Answer

um i think its 29+28+27+26+25+24+23+22+21+20+19+18+17+16+15+14+13_+12+11+10 weel you get the picture keep going till you get to one i think thats it

Anonymous · Answer

156

A Girl Who Snowboards · Answer

870

  But thats not if you count the teacher.

~Minty♥ · Answer

435
465 including the teacher??

Aiko K · Answer

Uhhh,,,, 119 possible trades?? o__O

! Nikki · Answer

435 perhaps? 
But the tallest kid can't do it.

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Hmm... Here's a riddle...?

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