Question

A bag contains 7 red marbles, 3 blue marbles and 5 green marbles. If two marbles are drawn out of the bag, replacing them after each draw, what is the EXACT (simplified fraction) probability that both marbles drawn will be green?

Answer 1

P = (5/15) x (5/15)

= (1/3) x (1/3)

= 1/9

The probability they will both be green is 1/9 or 1 in 9.