Question:
A's income is 20% less than that of B. By what per cent is B's income more than A's?
Solution:
Let B's income be Rs 100
Then, A's income $=$ Rs 80
Therefore, B's income is more than A's income by $=\frac{(100-80)}{80} \times 100 \%$
$=\frac{20}{80} \times 100 \%=25 \%$
= RS 125
$\therefore$ B's income is more than that of A's by $(125-100) \%$, i.e., $25 \%$.