Question

Can someone please help!!!!!

If the length and width of a rectangle are each increased by ten percent, then the perimeter of the rectangle is increased by what percent?

Answer 1

The answer is 10%

Explanation:

Let the length of the rectangle is x

Let the width of the rectangle is y

∵ They will increase by 10% each

∴ The new length = x × 110/100 = 1.1x

∴ The new width = y × 110/100 = 1.1y

∵ The old perimeter = 2(x + y) = (2x + 2y)

∴ The new perimeter = 2(1.1x + 1.1y) = 1.1(2x +2y)

∴ The new perimeter is greater than the old perimeter by 1.1 - 1 = 0.1

∴ The percentage of increasing in the perimeter = 0.1 × 100 = 10%