A bag contains 3 blue, 2 green and 5 red balls. If four balls are picked at random, what is the probability that two are…

In a drawer there are 5 black socks and 3 green socks. Two socks are picked randomly one after the other without replace…

In a school, 45% of the students play football, 30% play volleyball and 15% both. If a student is selected at random, th…

For a random variable X, E(X) is

Find the probability that getting 4 digit number with 1 in the unit place and 2 in the tens place when the numbers 1, 2,…

The mean of binomial distribution is

The probability that A speaks truth is $$\frac{{3}}{{5}}$$ and that of B speaking truth is $$\frac{{4}}{{7}}$$. What is …

An urn contains 6 red, 4 blue, 2 green and 3 yellow marbles. If two marbles are picked up at random, what is the probabi…