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? If 6 more black balls are put in the box, the probability of drawing a black ball is now double of what it was before. Find x.

A box contains 12 balls, out of which x are black, (i) If one ball is drawn at random, what is the probability that it will be a black ball? (ii) If 6 more black balls are put in the bag, the probability of drawing a black ball will double than that in (i), find x.

A bag contains 2 red balls and 4 black balls. A ball is drawn at random from the bag. What is the probability that the ball drawn is red?

A bag contains 12 blue balls and x red balls. If one ball is drawn at random (i) what is the probaility that it will be a red ball ? (ii) If 8 more red balls are put in the bag, and if the probability of drawing a red ball will be twice that of the probaility in (i), then find x.

A bag contains 2 red balls and 6 black balls. A ball is drawn at random from the bag. What is the probability that the ball drawn is not red?

A bag contains 3 red balls and 5 black balls. A ball is selected at random from the bag. What is the probability that the ball selected is (i) red ? (ii) not red?

A bag contains 5 black balls, 4 white balls and 3 red balls. If a ball is selected at random, the probability that it is not red is ..........

A bag contains 3 red , 3 white and 3 green balls. One ball is taken out of the bag at random. What is the probability that the ball drawn is - red.

A bag contains 5 red balls, 6 white balls, 7 green balls, 8 black balls. One ball is drawn at random from the bag. Find the probability that the ball drawn is (i) white (ii) black or red (iii) not white (iv) neither white nor black