Question

A group consists of 12 persons, of which 3 are extremely patient, other 6 are extremely honest and rest are extremely kind. A person form the group is selected at random. Assuming that each person is equally likely to be selected, find the probability of selecting a person who is  extremely kind or honest. Which of the above you prefer more.  

Answer 1

Number of persons in the group = 12
∴ Total number of outcomes = 12

Number of persons who are extremely honest = 6
Number of persons who are extremely kind = 12 − (3 + 6) = 3
∴ Number of persons who are extremely kind or honest = 6 + 3 = 9
So, the favourable number of outcomes are 9.
∴ P(selecting a person who is extremely kind or honest) =\[\frac{\text{ Favourable number of outcomes }}{\text{ Total number of outcomes }} = \frac{9}{12} = \frac{3}{4}\]