Since we have given that
If length is increased by 25%
If breadth is decreased by 20%
So, net change in area of rectangle would be
25-20-(25*20)/100
=5-500/100
=5-5
=0%
to illustrate, you can draw a rectangle with the length 8 and the width 4
area=8*4=32
then you draw new rectangle ( if the length increase by 25% and breadth is decreased by 20%) which will have:
the length 8+0.25*8= 10
and the width 4-0.20*4=3.2
area=10*3.2=32
as you can see both areas are same, so net change in area of rectangle is 0%
