Q. 5 An urn contains balls of which balls bear a mark and the remaining bear a mark A ball is drawn at random from the urn, its mark is noted down and it is replaced. If balls are drawn in this way, find the probability that
(i) all will bear mark.
Total balls in urn = 25
Balls bearing mark 'X' =10
Balls bearing mark 'Y' =15
balls are drawn with replacement.
Let Z be a random variable that represents a number of balls with Y mark on them in the trial.
Z has a binomial distribution with n=6.