In a bag there are a certain number of yellow balls and blue balls. The probability of picking up exactly 1 blue ball when 2 balls are randomly drawn, is 1/2. Which of the following is the ratio of the number of yellow balls to blue balls in the bag Choose the correct option:
A) 3:1	B) 1:3	C) 1:5	D) 1:1	E) 3:1
since the probability of drawing a blue ball out of two picks is 1/2.   the ratio of the blue ball to yellow balls should be 1:1   Answer : 1:1
<result>D</result>
In a bag there are a certain number of yellow balls and blue balls. The probability of picking up exactly 1 blue ball when 2 balls are randomly drawn, is 1/2. Which of the following is the ratio of the number of yellow balls to blue balls in the bag