Question

A number is increased by $20\%$ and then decreased by $20\%$. Find the net increase or decrease per cent.

Answer 1

Let the number $=100$
$\therefore$ Number after 20% increase $=100+20=120$
Decrease in the new number
$=20\%$ of $120=\frac{120}{100}\times 120=24$
$\therefore$ Final number $=120-24=96$
$\therefore$ Net decrease $=100-96=4$
Hence, there is a net decrease of $4\%$.