30 basketballs (15 Spalding, 10 Wilson, and 5 other brand-name balls) are on a basketball court. Barry Wood closes his eyes and arbitrarily picks up a ball from the court. Determine the probability that the ball selected is

a Wilson or a Spalding.

2 answers

prob = 25/30 = 5/6
Let U = {5, 10, 15, 20, 25, 30, 35, 40}

A = {5, 10, 15, 20}

B = {25, 30, 35, 40}

C = {10, 20, 30, 40}.

Find A ⋂ B.