Re: The length of a rectangle A is decreased by 40% and width increased by
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01 May 2023, 12:56
OE
We know that the area of rectangle = length × width
Given length is decreased by 40% that means the area is decreased by 40%
And width is increased by 50% that means the area is increased by 50%
Now, we know that if something changes by 𝑥% and then changes by 𝑦% then the
net percent change is given by
Net percent change = (𝑥 + 𝑦 +𝑥𝑦/100) %
So, the net percent change in the area of A = (- 40 + 50 +(−40)(50)/100) %
(negative sign indicates decrease in value) = (10 – 20) % = - 10% i.e. 10 % decrease = 90% of the area of rectangle A