Question

A's income is 20% less than that of B. By what per cent is B's income more than A's?

Answer 1

$$\begin{gathered} \mathrm{Let}\mathrm{B}\text{'}\mathrm{s}\mathrm{income}\mathrm{be}\mathrm{Rs}100 \\ \mathrm{Then},\mathrm{A}\text{'}\mathrm{s}\mathrm{income}=\mathrm{Rs}80 \\ \mathrm{Therefore},\mathrm{B}\text{'}\mathrm{s}\mathrm{income}\mathrm{is}\mathrm{more}\mathrm{than}\hspace{0.17em}\mathrm{A}\text{'}\mathrm{s}\mathrm{income}\mathrm{by}=\frac{\left(100-80\right)}{80}\times 100\% \\ =\frac{20}{80}\times 100\%=25\% \end{gathered}$$
$=Rs125$
$\therefore \mathrm{B}\text{'}\mathrm{s}\mathrm{income}\mathrm{is}\mathrm{more}\mathrm{than}\mathrm{that}\mathrm{of}\mathrm{A}\text{'}\mathrm{s}\mathrm{by}\left(125-100\right)\%,\mathrm{i}.\mathrm{e}.,25\%.$