combinatorics 4

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combinatorics 4

by Gurpinder » Thu Jul 29, 2010 7:47 am
Meredith and 5 of her friends are taking a road trip in their minivan. If each row holds 3 people, how many different rows of 3 people can be filled?

oa: 20

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by kmittal82 » Thu Jul 29, 2010 8:04 am
I think it boils down to selecting 3 people from 6
= 6C3 = 6!/(3!3!) = 20

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by Gurpinder » Thu Jul 29, 2010 8:09 am
omg.....

i made a silly error. i wasn't counting medrith in the 5 friends. hahahahha....... someone just kill me :(

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by kmittal82 » Thu Jul 29, 2010 8:37 am
lol, it happens my friend. Ive managed to mess up a simple 10/2 calculation in the past before :D