Problem Solving

A certain basket contains 10 apples, 7 of which are red and 3 of which are green. If 3 different apples are to be selected at random from the basket, what is the probability that 2 of the apples selected be red and 1 will be green?

a)7/40 b)7/20 c)49/100 d)21/40 e) 7/10

please provide explainations.

thanks.

answer is (7c 2* 3 c 1)/ 10 c 3 = 21/40

gmat guy....can you please elaborate on your explaination...

thanks.

2 red out of 7 gives 7c2
1 green out of 3 gives 3c1
3 apples out of 10 gives 10c3

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

(7c2* 3c1)/ 10c3 = 21/40