SSC CHSL 17 Mar 2020 Shift 2 Paper

Let the number be $\mathit{x}$.
We know that,
Dividend $=$ Divisor $\times$ quotient $+$ Remainder
$\mathit{x}=3\mathit{k}+2$ ...(i)
According to the question,
$\mathit{x}+5=3\mathit{k}+2+5$
$\mathit{x}+5=3\mathit{k}+7$
$\mathit{x}+5=3\left(\mathit{k}+2\right)+\underset{\mathrm{Remainder}}{\underset{\downarrow }{1}}$
Hence, when 5 is added to the number, then the remainder will be 1.