Question

A box contains 12 balls of which some are blue in colour. If 6 more blue balls are put in the box and a ball is drawn at random, the probability of drawing a blue ball doubles than what it was before. Find the number of blue balls in the bag. Please follow me.......​

Answer 1

Answer:

Answer:

3 blue balls

Step-by-step explanation:

Let the number of blue balls in the bag = x.

Total number of balls = 12

Probability of getting a blue ball = x/12.

6 more blue balls are put in the box. Additionally 6 balls are added.

Total number of balls = 18.

Number of blue balls = x + 6

Probability = (x + 6)/18

Then,

Probability of drawing a blue ball doubles than what it was before.

=> 2 * (x/12) = (x + 6)/18

=> (x/6) = (x + 6)/18

=> 18x = 6x + 36

=> 12x = 36

=> x = 3

Hence, there are 3 blue balls in the bag.