Question

1500 families with 2 children were selected randomly, and the following data were recorded:

$\begin{array}{cccc}\text{Number of girls in a family}& 2& 1& 0\\ \text{Number of families}& 300& 500& 700\end{array}$

Compute the probability of a family chosen at random having 2 girls.

• A. $\frac{1}{5}$
• B. $\frac{1}{3}$
• C. $\frac{7}{15}$
• D. $\frac{8}{15}$

Answer 1

The correct option is A

$\frac{1}{5}$

Probability = $\frac{Numberoffavourableoutcomes}{Totalnumberofoutcomes}$

The total number of families = 300 + 500 + 700 = 1500

The families which have two girls = 300

P (Number of families having two girls) $=\frac{300}{1500}$ $=\frac{1}{5}$