Question

In a class of $40$ students, $\frac{1}{5}$ of the total number of students like to eat rice only, $\frac{2}{5}$ of the total number of students like to eat chapati only and the remaining students like to eat both. What fraction of the total number of students like to eat both?

Answer 1

Total number of students $=40$
Students who eat rice only $=\frac{1}{5}$ of total students
$=\frac{1}{5}\times 40=8$
Students who eat chapati only $=\frac{2}{5}$ of total students
$=\frac{2}{5}\times 40=16$
$\therefore$ Students who eat both chapati and rice
$=$ Total number of student$-$ (students who eat rice only $+$ Students who eat chapati only)
$=40-(8+16)$
$=40-24=16$
$\therefore$ fraction of students who eat both chapati and rice
$=\frac{\text{Number of students eat both chapati and rice}}{\text{Total number of students}}$
$=\frac{16}{40}$
$=\frac{2}{5}$