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Norman window

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Norman window

by vladmire » Mon Jan 19, 2009 9:20 am
A norman window consists of a retangle surmounted by a semicircle. Find the area of the norman window. How much wood fram is needed to enclose the window?

L-6
W-4

I got the rectangle part of the proble...
A=LW
A=6*4=24
24+2Pi=30.28

How do I get the semicircle?
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by logitech » Mon Jan 19, 2009 9:32 am
This should help
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Re: Norman window

by coffee5251 » Thu Jan 29, 2009 5:26 pm
vladmire wrote:A norman window consists of a retangle surmounted by a semicircle. Find the area of the norman window. How much wood fram is needed to enclose the window?

L-6
W-4

I got the rectangle part of the proble...
A=LW
A=6*4=24
24+2Pi=30.28

How do I get the semicircle?
Why do you add 2Pi to the area? How do you know what the radius of semicrircle is?

Also can you explain why you would find the hypotenuse of the triangle? How is that related to the window frame?
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by umaa » Thu Jan 29, 2009 6:55 pm
A rectangle SURMOUNTED by a semi circle. So, the semicircle is on top of the rectangle.

Area of norman window is, Area of rec + Area of S.circle.

Area of S. circle is, (pi * r^2)/2; r = l/2 = 6/2 = 3

= 6*4 + pi * 9/2

Total area = = 24 + 4.5pi


To find the wood frame needed to enclose the window is to add rectangle's perimeter and the length of the arc.

= peri. of rec + length of arc
= 2 (6+4) + 2*pi*3/2
= 20 + 3*pi

Guys, let me know the OA.
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by krisraam » Thu Jan 29, 2009 8:27 pm
I think this is ambiguous.

Answer is either 20 + 3pi or 20 + 2Pi depending on where the semi circle is surmounted. If the semicircle over the length its 20+3pi. if its over the width its 20+ 2Pi.

Thanks
Raama
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