Question

4. A box contains 12 balls out of which x are black. If one ball is drawn at random from the
box, what is the probability that it will be a black ball?

1f 6 more white balls are put in the box, the probability of drawing a black ball is now
double of what it was before find x​

Answer 1

Step-by-step explanation:

Total number of balls = 12

Total number of black balls = x

P (getting a black ball) = x/12

If 6 more black balls are put in the box, then

Total number of balls = 12 + 6 = 18

Total number of black balls = x + 6

P (getting a black ball now) = x + 6 /18

Atq,

2(x/12) = ( x+. 6 /18)

3x = x+6

2x=6

x = 3