% change in the area

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% change in the area

by sanju09 » Wed Feb 25, 2009 2:32 am
What is the % change in the area of a rectangle when its length increases by 10% and its width decreases by 10%?

A. 0%
B. 20% increase
C. 20% decrease
D. 1% decrease
E. Insufficient data
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by bmlaud » Wed Feb 25, 2009 2:43 am
IMO D

Initial area L*B

After changes 1.1 L * 0.9 B = 0.99 L*B

Decrease in area 0.01 L*B
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Re: % change in the area

by sureshbala » Wed Feb 25, 2009 2:59 am
sanju09 wrote:What is the % change in the area of a rectangle when its length increases by 10% and its width decreases by 10%?

A. 0%
B. 20% increase
C. 20% decrease
D. 1% decrease
E. Insufficient data
Let L = 10 and B= 10. Area = 100
Now L =11 and B = 9. Area = 99.

So 1% decrease

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by Mr2Bits » Wed Feb 25, 2009 9:58 am
D you can test this to make it easier