If each side of a square is increased by 25%, find the percentage change in its area?

let each side of the square be a , then area = $a2$ 

As given that The side is increased by 25%, then 

New side = 125a/100 = 5a/4 

New area =  $\frac{5a}{4}2$  

Increased area=  $\frac{25a2}{16}-a2$ 

Increase %= $\frac{9a2/16}{a}*100$  % = 56.25%