Question

a number is first increased by 25% and then decreased by 25%. find the net increase or decrease percent

Answer 1

25% of x = 0.25 * x

25% of '0.25x' = 0.25*0.25*x

=0.0625 * x

so if x=100
then 25% of 25% of 100 = 0.0625 * 100 = 6.25

Answer 2

Let the original number be x.

Given the number increased by 25% = x + 0.25x = 1.25x.

Given the number decreased by 25% = 1.25 - 0.25(1.25) 

                                                                = 0.9375.

% change = x - 0.9375/x * 100%

                 = 0.0625 * 100%

                 = 6.25.

The decrease % is 6.25.


Hope this helps!