Question

In a particular section of Class IX, $40$ students were asked about the months of their birth and the following graph was prepared for the data so obtained:

Find the probability that a student of the class was born in August.

Answer 1

Total number of students in IX class$=40$
∴ $n\left(S\right)=40$
Number of students born in August$=6$
∴ $n\left(E\right)=6$

Now,
$P\left(E\right)=\frac{n\left(E\right)}{n\left(S\right)}$
$\Rightarrow P\left(E\right)=\frac{6}{40}$
$\Rightarrow P\left(E\right)=\frac{3}{20}$

Thus, probability that a student of the class was born in August is $\frac{3}{20}$.