In a binomial distribution, the mean is $${2 \over 3}$$ and the variance is $${5 \over 9}$$. What is the probability that X = 2 ?

The probability that a ship safely reaches a port is $${1 \over 3}$$. The probability that out of 5 ships, at least 4 ships would arrive safely is

What is the probability that at least two persons out of a group of three persons were born in the same month (disregard year) ?

If $$P(B) = {3 \over 4}$$, $$P(A \cap B \cap \overline C ) = {1 \over 3}$$ and $$P(\overline A \cap B \cap \overline C ) = {1 \over 3}$$, then what is $$P(B \cap C)$$ equal to ?