The length of a rectangle is increased by 10% and the width by 20%. What is the percentage change in area?

The length of a rectangle is increased by 10% and the width by 20%. Determine the percentage change in area.

Answers

Previous are = Length x Width = L X W = LW

New Area =

$(\frac{110}{100}L) \times (\frac{120}{100}W) \ = \ 1.32LW$

Change in Area= 1.32LW -LW = 0.32LW

Percentage Change in Area =

$\frac {0.32LW}{LW} \times 100$

= 32%

raphael answered the question on January 17, 2017 at 05:32

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