Question

The length of a rectangle is increased by 60%. By what percent the width have to be decreased to maintain the same area?

• A. 37 1/2 %
• B. 60%
• C. 75%
• D. 120%

Answer 1

Answer:

A. 37 1/2 %

Solution: Given: The length of a rectangle is increased by 60%. Formula used: Area of rectangle = l × b; where l, b are length and breadth of rectangle. Calculation: Let the length of the rectangle = 100m Breadth of rectangle = 100m Original area = 100 × 100 = 10000 m2 New length = 160 m Let new breadth = x New area = 160x ∴ Area remains same, ⇒ 10000 = 160x ∴ x = 125/2 ∴ Decrease in breadth = (100 - 125/2)% = 37.5%