A bag contains 3 black, 4 white and 2 red balls, all the balls being different. The number of selections of at most 6 balls containing balls of all the colours, is

A bag contains 3 black, 4 white and 2 red balls, all the balls being different. The number of at most 6 balls containing balls of all the colours is

A bag contains 5 black balls, 4 white balls and 3 red balls. If a ball is selected random wise the probability that it is black or red ball is

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 a black or a red ball is

A bag contains 4 red, 6 white and 5 black balls. 2 balls are drawn at random. The probability of getting one red and one white ball is

A bag contains 4 red, 3black and 2 white balls. If 3 balls are selected at random, the probability of selecting atleast one white ball is

A bag contains 3 red, 4 white and 6 blue balls. 3 balls are drawn at random. The probability that they are of different colours is

A bag contains some white and some black balls, all combinations of balls being equally likely. The total number of balls in the bag is 10. If three balls are drawn at random without replacement and all of them are found to be black, the probability that the bag contains 1 white and 9 black balls is

A bag contains 8 red, 3 white and 9 blue balls. If three balls are drawn at random, determine the probability that all the balls are of different colour.

A bag contains 4 white balls and 3 black balls. If two balls are drawn at random, then mean of number of white balls is