SOLUTION: If Length of a rectangle is increased by 20% and width is decreased by 20% , then area will be ?

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Question 550052: If Length of a rectangle is increased by 20% and width is decreased by 20% , then area will be ?
Found 2 solutions by plover, MathTherapy:
Answer by plover(15) About Me  (Show Source):
You can put this solution on YOUR website!
Let the original length and breadth be l and b respectively . Hence initial area is lb
hence the new length is +l%281%2B20%2F100%29+ = +l%28120%2F100%29 = 6l%2F5
hence new breadth will be +l%281-20%2F100%29=l%2880%2F100%29=4b%2F5
hence new area is 6l%2F5%2A4l%2F5=24%2Alb%2F25
Hence the area decreases .
Decrease in area = lb-24lb%2F25=lb%2F25
hence % decrease =lb%2F25%2Flb%2A100=4+%25 %

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!

If Length of a rectangle is increased by 20% and width is decreased by 20% , then area will be ?

Let length = L, and width = W
Then, original area = LW

Increasing length by 20% makes the new length 1.2L
Decreasing width by 20% makes the new width .8W
New area = 1.2L(.8W), or .96LW

This means that the area would DECREASE by 4% (LW - .96LW)

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