Question

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

Answer 1

38,760


77,520


1,860,480


27,907,200

it is either a or d, depending if it is combination or permutations

Answer 2

but I don't know which one

Answer 3

\(\Large{_nC_r =} \dfrac{n!}{r!(n-r)!}\)

Answer 4

substitute r = 6 and n = 20

Answer 5

\(\Large{_nC_r =}\)\(\dfrac{20!}{6!(20 - 6)!}\)\(\Large{ = 38760}\)

Answer 6

@mehek14 thank you!