Question

If the length of a rectangle is decreased by 60% and the width is increased by 30%. What will be the percentage change in the area of the rectangle?​

Answer 1

Answer:

Let the original length be L and width W

Original area = L×W

If the length is decreased by 60% then new length becomes 0.4×L and similarly width becomes 1.3×W

So new area becomes 0.4L × 1.3W= 0.52 LW

So change in area = L× W - 0.52 LW = 0.48LW

So % change = (0.48LW/ LW)×100 = 48%

Answer 2

The area will decrease by 48%.

Given:

The length of the rectangle decreased by 60%.

The width of the rectangle increased by 30%.

To Find:

The percentage change in the area of the rectangle.

Solution:

Let us assume the length of the rectangle is l and the width is w.

So, the area = lw

After being decreased by 60% the new length is $(l-0.6l)=0.4l$

After getting increased by 30% the new width is $(w+0.3w)=1.3w$

The new area will be (0.4l × 1.3w)= 0.52lw

The change in area is (lw-0.52lw)= 0.48lw

Hence, the area will decrease by 48%.

#SPJ2