In how many ways can a teacher arrange 6 students in the front row of a classroom with a total of 20 students?

Question

agent0smith · Answer

Combinations, order doesn't matter - from 30 people choose 5... 30C5 if you don't know the formula: http://www.mathsisfun.com/combinatorics/images/combinations-no-repeat.png n is the total - 30 people. r is the number you're choosing - 5.

anonymous · Answer

ok thanks so much!

anonymous · Answer

what about In how many ways can a teacher arrange 6 students in the front row of a classroom with a total of 20 students?

agent0smith · Answer

raden · Answer

in the first 6, we can select 6!, and the rest is 14!
then times them

agent0smith · Answer

@RadEn  ^ you mean divide them...?

raden · Answer

no, i mean multiply between the first 6 rows and the last 14 rows. then by using filling slot method, it like  :

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