SOLUTION: If lenght of a rectangle is increased by 30% and the width is decreased by 20% then by what percentage the area of rectangle is increased ?

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Question 838225: If lenght of a rectangle is increased by 30% and the width is decreased by 20% then by what percentage the area of rectangle is increased ?
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
L= original length of the rectangle
W= original width of the rectangle

Then,
L%2AW= original area of the rectangle
1.3L= original length increased by 30%
0.8W= original width decreased by 30%
%281.3L%29%2A%280.8W%29= final area of the modified rectangle
%281.3L%29%2A%280.8W%29=1.04%2AL%2AW= final area of the modified rectangle
1.04%2AL%2AW-L%2AW=%281.04-1%29%2AL%2AW=0.04%2AL%2AW= area increase
0.04%2AL%2AW%2F%28L%2AW%29=0.04=4%2F100=highlight%28%224+%25%22%29= area increase as a fraction or percent of the original area