Question

The following table shows number of males and females of a locality in different age groups.

$\begin{array}{cccc}\text{Age in years}& 10-20& 21-50& \text{Above}50\\ \text{Male}& 15& 16& 9\\ \text{Female}& 8& 20& 12\end{array}$

If one person is selected at random, find the probability of getting a person with age 21-50.

• A. $\frac{1}{5}$
• B. $\frac{1}{20}$
• C. $\frac{11}{20}$
• D. $\frac{9}{20}$

Answer 1

The correct option is D

$\frac{9}{20}$

Total number of people in the given locality = 15 + 16+ 9 + 8 + 20 + 12

= 80

Number of persons with age 21-50 = 16+ 20

= 36

$\text{Probability to get a male}=\frac{\text{Number of favourable outcomes}}{\text{Total number of possible outcomes}}$

$=\frac{\text{Number of persons with age 21-50}}{\text{Total number of people in the given locality}}$

= $\frac{36}{80}$

= $\frac{9}{20}$