Question
A box contains 10 red balls, 12 green balls, and 8 blue
balls. Two balls are drawn at random. What is the probability that both balls drawn are either red or green?Solution
Total balls = 10 + 12 + 8 = 30. P(both red or green) = P(both red) + P(both green). P(both red) = (10/30) * (9/29) = 90/870. P(both green) = (12/30) * (11/29) = 132/870. P(both red or green) = 90/870 + 132/870 = 222/870 = 37/145. Correct Option: d
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