25. A bag contains 12 red marbles, 14 yellow marbles, and 8 green marbles. How many additional red marbles must be added to the 34 marbles already in the bag so that the probability of randomly drawing a red marble is ?

Answer and Explanation

Your Answer is

Correct Answer is B

Explanation

Assume the added red ball is x, (12+x) ÷ (34+x) = 3/5

102+3x = 60+5x, x=21