triangle area

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triangle area

by mehrasa » Wed Nov 16, 2011 8:22 pm
if the altitude of a triangle increase by %8 and its base increase by %6.. how many percent area of triangle increase?



please give me ur approach to find this
this is my approach
original triangle area = 1/2(bh)=0.5 bh
enlarged triangle area= 1/2 (1.06b*1.08h)= 1/2(1.448bh)= 0.724bh
==>0.724-0.5/0.5==> 0.224/0.5= 0.448 ==> 44% increase
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by shankar.ashwin » Wed Nov 16, 2011 9:21 pm
As you find only a ratio, you can neglect the 1/2 in the formula as it would get cancelled anyways.

Use easy numbers. Let b=h=10 (b*h = 100)

Now new b = 10.8 and new h =10.6 (b*h = 114.48)

% increase = 14.48

P.S In your calculation - 1.08*1.06 = 1.1448 and not 1.448. Your method is correct though
mehrasa wrote:if the altitude of a triangle increase by %8 and its base increase by %6.. how many percent area of triangle increase?



please give me ur approach to find this
this is my approach
original triangle area = 1/2(bh)=0.5 bh
enlarged triangle area= 1/2 (1.06b*1.08h)= 1/2(1.448bh)= 0.724bh
==>0.724-0.5/0.5==> 0.224/0.5= 0.448 ==> 44% increase

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by MBA.Aspirant » Wed Nov 16, 2011 10:08 pm
let height = 4 and base = 3, area = 1/2 * 3 * 4 = 6

height increased by 0.08 = 4 * 1.08 = 4.32

base increased by 0.06 = 3 * 1.06 = 3.18

area = 1/2 * 3.18 * 4.32 = 6.87

% increase = 0.87/6 = 14.5 %