Question:
The value of $S$ in $\frac{1}{3}+S=\frac{2}{5}$ is
(a) $\frac{4}{5}$
(b) $\frac{1}{15}$
(c) 10
(d) 0
Solution:
(b) Given, $\frac{1}{3}+S=\frac{2}{5}$
$\Rightarrow \quad S=\frac{2}{5}-\frac{1}{3}$ $\left[\right.$ transposing $\frac{1}{3}$ to RHS $]$
$\Rightarrow \quad S=\frac{6-5}{15}$ [taking LCM in RHS]
$\therefore \quad S=\frac{1}{15}$