In a rectangle, if length is increased by 20% and breadth is decreased by 20%, what is the percentage change in area?
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Correct answer: A
Explanation
Increase in length = 20%
Decrease in width = 20%
According to the formula:
New Area = (1 + a/100)(1 − b/100) × Original Area
= (1 + 20/100)(1 − 20/100)
= 1.2 × 0.8
= 0.96
Change = 0.96 − 1 = −0.04
Percentage Change = 4% decrease