Question

if the area of a square increases by 27.69% what is the percentage change in its perimeter?

Answer 1

Let the area of square be 10,000(side*side) sq mts.
Then the length of its side = 100 mts and perimeter = 400 mts
If the area is increased by 27.69% then the new area = 12769 sq mts.
If area = 12769 then,length of new side is $\sqrt{12769}$ = 113 m 
New perimeter = 4*side = 452 mts
% change in perimeter = [(452-400)/400]*100 = 13%