Question

In how many ways can a gymnastics team of 4 be chosen from 9 gymnasts?

36
126
3,024

Answer 1

1st team memeber - how many choices of gymnastics u get?

Answer 2

Idk :/

Answer 3

9 right?

Answer 4

Yeah

Answer 5

second member? how much choices are left?

Answer 6

8?

Answer 7

Correct :) so for 4 members, it would be 9x8x7x6 BUT.....

Answer 8

it would be 3024

Answer 9

Let's say the team selected is A,B,C,D....does it make any difference whether it is ABCD or DCBA?

Answer 10

Now...remember i said BUT :P 3024 is too many because you are double counting ABCD and DCBA - that should be counted as 1

Answer 11

OHhhhhhh

Answer 12

It is Combination and you have to divide by 4x3x2x1 to get the right answer. The general eqn is:

nCr = n!/r!(n - r)!