A bag contain `40` balls out of which `15` are black,then probability of a ball not black is

Consider a bag containing 10 balls of which a few are black balls. Probability that bag contains exactly 3 black balls is 0.6 and probability of bag containing exactly 1 black ball is 0.4. Now, balls are drawn from the bag, one at a time, with out replacement, till all black balls have been drawn.Find the probability that this procedure would end at the 6^(th) draw.

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

A bag contains 15 white balls and some black balls. If the probability of drawing a black ball is thrice that of a white ball, find the number of black balls in the bag.

A bag contains 15 white balls and some black balls. If the probability of drawing a black ball is thrice that of a white ball, find the number of black balls in the bag.

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 3 red,4 white and 7 black balls.The probability of drawing a red or a black ball is

A bag contains 15 white and some black balls. If the probability of drawing a black ball from the bag is thrice that of drawing a white ball find the number of black balls in the bag.

A bag contains 15 white and some black balls. If the probability of drawing a black ball from the bag is thrice that of drawing a white ball, find the number of black balls in the bag.

A bag A contains 5 white and 6 black balls. Another bag B contains 4 white ad 3 black balls. A ball is transferred from the bag A to the bag B and then a balls is taken out of the second bag. Find the probability of this ball being black.

A bag A contains 5 white and 6 black balls. Another bag B contains 4 white and 3 black balls. A ball is transferred from bag A to the bag B and then a ball is taken out of the second bag. Find the probability of this ball being black.