Question

If the length of a rectangle is increased by 30%
and the breadth is decreased by 30%, then the
area.?
Explain in brief. ​

Answer 1

Let L be the length and B be the breadth

Area = LB

After change,

length becomes 1.3L

breadth becomes 0.75B

Area = 1.3L × 0.75B = 0.975LB

Change in area = (0.975LB - LB)/LB × 100

= -2.5%

Thus, 2.5% decrease in the area

Answer 2

Let L be the length and B be the breadth

Area = LB

After change,

length becomes 1.3L

breadth becomes 0.75B

Area = 1.3L × 0.75B = 0.975LB

Change in area = (0.975LB - LB)/LB × 100

= -2.5%

Thus, 2.5% decrease in the area