Find the probability that in a family of 4 children there will be (a) at least 1 boy (b) atleast 1 boy and 1 girl. Assume that the probability of a male is 1/2.

An insurance salesperson sells policies to 5 men, all of identical age and in good health. According to the actuarial tables, the probability that a man of this particular age will be alive 30 years is 2/3 : Find the probability that in 30 years (a) all 5 men, (b) at least 3 men, (c) only 2 men, (d) none will be alive

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