A box contains 5 red, 3 green and 4 blue balls. A boy is allowed to take away two balls from the box.What is the probability that one is green and the other is blue?
A. \(\frac{2}{11}\) B. \(\frac{5}{12}\) C. \(\frac{8}{12}\) D. \(\frac{7}{11}\)
Correct Answer: A
Explanation
Total number of balls = 5 + 3 + 4 = 12 balls P(one ball is green and the other is blue) = P(first ball is green and second blue) + P(first ball is blue and the second green) = \(\frac{3}{12} \times \frac{4}{11} + \frac{4}{12} \times \frac{3}{11}\) = \(\frac{2}{11}\)
