Question

A bag contains 4 white and 6 black balls. Two balls are drawn without replacement. What is the probability that both are white?

Solution

1. Probability of drawing a white ball first = 4/10.
2. After one white ball is drawn, 3 white balls remain out of 9 total balls.
3. P(both white) = 4/10 x 3/9 = 12/90 = 2/15.