Question

How do you solve something like: Charlie has 13 socks in his drawer, 8 blue and 5 green. He selects 5 socks at random. Find the probability that he gets
a. Two blue socks and three green socks

Answer 1

type in 8C2 multiplied by 5C3. c stands for combination. do you have a graphing calculator or do you have to do this by hand?

Answer 2

I have to do it by hand.... :/

Answer 3

i'm sorry. in that case, the formula for a combination is n!/k! (n-k)!
in the problem 8C2 x 5C3, you have to do each separately, then multiply them afterwards
the 8 is the n, and the 2 is the k
so 8!/2! (8-2)!
(8! represents 8x7x6x5x4x3x2x1)
you get 40320/2x720 or 28
do the same for the other combination, you get 10
28 x 10 = 280.
this number is 280 out of 1287 (the total number of combinations possible)

Answer 4

Thank you!