Question

A number is increased by 20% and the increased number is decreased by 20%.Find the increase or decrease percent.

Answer 1

Let the number be $=100$

Increase in the number $=20\%of100$

$=\frac{20}{100}\times 100$

$=20$

Increased number $=100+20$

$=120$

The resulting number decreased by $20\%$

Decrease in the number $=\frac{20}{120}\times 120$

$=24$

New number $=120-24$

$=96$

Now, net decrease $=100-96$

Net % decrease $=\frac{Netdecrease}{Originalnumber}\times 100$

$=\frac{4}{100}\times 100$

$=4\%$

Hence the net percent decrease is $4\%$.