Question

A number is increased by 20% and then decreased by 20%. Now it is again increased by 20% and then decreased by 20%. The net increase or decrease percent in the number is:

Answer 1

Answer:

7.84% Decrease

Step-by-step explanation:

Let say number = x

Increased by 20% so it become = x ( 1 + 20/100) = 1.2x

Now decreased by 20 % so it becomes = 1.2x ( 1- 20/100) = 1.2x * 0.8 = 0.96x

Now increased by 20 %  so it becomes = 0.96x (1+ 20/100) = 0.96x * 1.2

= 1.152x

Now decreased by 20% so it becomes =  1.152x ( 1 - 20/100) = 1.152x * 0.8

= 0.9216x

Decrease in number = x - 0.9216x = 0.0784x

% Decrease = (0.0784x/x)*100 = 7.84 %