Question

A rectangle has it length increased by 20% and width decreased by 20%. Find if any, the percentage
change in its area​

Answer 1

Step-by-step explanation:

Consider the length and the width of the rectangle before making by 20%.

The new length is a+(20/100)*a [because its increased by 20%of before length]=1.2a.

The new width is b-(20/100)*b [because its decreased by 20% of before width]=0.8b.

Now the area of the rectangle whose sides are changed is=1.2ax0.8b=0.96ab.

To find the change in area=[( 0.96ab-ab)/ab]*100=-4%

The negative symbol indicates that there is a decrease in area of the new rectangle.

So the final answer is the area of the rectangle after changing the length and width is 0.96 times its original area and there is a reduction of area of 4% when compared to the original area.