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#1 2010-07-04 02:57:43
- haftakhan
- Member
- Registered: 2010-06-28
- Posts: 30
Help Needed
ABC is a triangle with height of 4 cm and base of 7 cm,drawn to a scale of 1cm:3km. Find the actual area of the triangle.
How to solve such question ?
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#2 2010-07-04 03:10:14
- ZHero
- Real Member
- Registered: 2008-06-08
- Posts: 1,889
Re: Help Needed
Just find the area of the triangle using...
Area=(Base*Height)/2
Now since the sides of the two triangles (the scaled down triangle and the actual larger triangle) are in the ratio 1cm:3km or 1cm:300000cm, the areas will be in the ratio 1²:300000². So multiply the area that you got above with 30000². Your answer will now be in cm². Change it to km².
Last edited by ZHero (2010-07-04 03:11:11)
If two or more thoughts intersect, there has to be a point!
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#3 2010-07-04 04:08:59
- haftakhan
- Member
- Registered: 2010-06-28
- Posts: 30
Re: Help Needed
if i do it this way will it be ok ?
1cm---->3km
So
4cm---->4*3=12km
7cm---->7*3=21km
Now Area=1/2bh
So A=1/2(21)(12)
A=126km Square
Is this right also ?
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#4 2010-07-04 05:30:22
- ZHero
- Real Member
- Registered: 2008-06-08
- Posts: 1,889
Re: Help Needed
Yeah Mr. Khan!
That's perfectly all right! Even looks cool... Neat! 
If two or more thoughts intersect, there has to be a point!
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