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
What is the % change in the area of a rectangle ........
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- neerajkumar1_1
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u can solve it by algebra...
but i suppose putting values will make it even more easy..
Let original L and B = 10
Area A = LB = 100
New Length L`= 1.1 * 10 = 11
New Breadth B` = .9 * 10 = 9
New Area A` = L` * B` = 99
Diff = A` - A = -1
the -ve sign signifies decrease
since there is a decrease
and the original value is 100
there is a 1 % dec
IMO D
but i suppose putting values will make it even more easy..
Let original L and B = 10
Area A = LB = 100
New Length L`= 1.1 * 10 = 11
New Breadth B` = .9 * 10 = 9
New Area A` = L` * B` = 99
Diff = A` - A = -1
the -ve sign signifies decrease
since there is a decrease
and the original value is 100
there is a 1 % dec
IMO D
thank you....but can you explain me in simple method.........neerajkumar1_1 wrote:u can solve it by algebra...
but i suppose putting values will make it even more easy..
Let original L and B = 10
Area A = LB = 100
New Length L`= 1.1 * 10 = 11
New Breadth B` = .9 * 10 = 9
New Area A` = L` * B` = 99
Diff = A` - A = -1
the -ve sign signifies decrease
since there is a decrease
and the original value is 100
there is a 1 % dec
IMO D