Question

A jar contains 6 chocolate chip cookies and 9 peanut butter cookies. Richard grabs 3 cookies at random to pack in his lunch. What is the probability that he drew 3 chocolate chip cookies?
A. 3/455
B. 4/91
C. 1/18
D. 1/2

Answer 1

Sample space = {6 cookies and 9 peanuts} = 15

1st draw :P(1 cookie) = 6/15
2nd draw P(also 1 cookie) = 5/14
3rd draw P(also 1 cookie) = 4/13

total probability = 6/15 x 5/14 x 4/13 = 4/91