Suppose that 5% of men and 0.25% of women have grey hair. A grey haired person is selected at random. What is the probability of this person being male? Assume that there are equal number of males and females.

A committee of two persons is selected from two men and two women. What is the probability that the committee will have no man?

A committee of two persons is selected from two men and two women. What is the probability that the committee will have one man?

Suppose that 6% of the perons with blood group O are left handed and 10% of those with other blood groups are left handed. It is given that 30% of the persons have blood group O. if a left handed person is selected at random. What is the probability that the person has blood group O.

Four persons are selected at random out of 3 men, 2 women and 4 children. The probability that there are exactly 2 children in the selection is:

There are 45 persons working in an office.If the number of females is 25 and the remaining are males,find the ratio of : the number of females to number of males.

From the employees of a company, 5 persons are selected to represent them in the managing committee of the company. Particulars of five persons are as follows: A person is selected at random from this group to act as a spokesperson. What is the probability that the spokesperson will be either male or over 35 years ?

In a class having 60% boys, 5% of the boys and 10% of the girls have an I.Q. of more than 150. A student is selected at random and found to have an I.Q. of more than 150. Find the probability that the selected student is a boy.

By examining the chest X-ray, the probability that TB is detected when is actually suffering from TB is 0.99 the probability of a healthy person diagonosed to have TB is 0.001. In a certain city, 1 in 1000 persons suffer from TB. A person is selected at random and is diagonsed to have TB. What is the probability that he/she actually sufferes from TB?