I am not sure about adding an image here.But here is the description . There is a square thats circumscribed by a circle(a square inside a circle) .
Q : Area of the square is 16 . What is the area of the circle?
a. 8 pie
b. 4 pie
c. 2 pie
d. pie
e. pie + 2
[/img]
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Deepthi Subbu
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goyalsau
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Where is the image......??????????????????Deepthi Subbu wrote:I am not sure about adding an image here.But here is the description . There is a square thats circumscribed by a circle(a square inside a circle) .
Q : Area of the square is 16 . What is the area of the circle?
a. 8 pie
b. 4 pie
c. 2 pie
d. pie
e. pie + 2
[/img]
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limestone
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Hi,
I cant see the picture. However, as far as I understand, the diagonal of the square is the diameter of the circle.
The square area = 16, thus the length of its side is 4, and the length of its diagonal is 4*sqrt2.
Thus the radius of the circle is half its diameter, or half the length of the square's diagonal:
=(4*sqrt2)/2 = 2*sqrt(2).
The area of the circle is:
= r^2*Pi = (2*sqrt2)^2*Pi = 8*Pi
Thus A should be the answer.
I cant see the picture. However, as far as I understand, the diagonal of the square is the diameter of the circle.
The square area = 16, thus the length of its side is 4, and the length of its diagonal is 4*sqrt2.
Thus the radius of the circle is half its diameter, or half the length of the square's diagonal:
=(4*sqrt2)/2 = 2*sqrt(2).
The area of the circle is:
= r^2*Pi = (2*sqrt2)^2*Pi = 8*Pi
Thus A should be the answer.
"There is nothing either good or bad - but thinking makes it so" - Shakespeare.
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Deepthi Subbu
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Hello limestone ,
You got the right answer . But how are u considering the diagonal to be the diameter of the circle??
You got the right answer . But how are u considering the diagonal to be the diameter of the circle??
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- here is the image that I was talking about
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MAAJ
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Because it's a square we know that if we cut the square in half we get a right triangle which sizes will be proportional in scale of 1:1:sqrt(2) (the sqrt(2) is for the side facing the 90 angle).
Knowing this we can determine that the diagonal of the square is 4*sqrt(2) which is the Diameter of the circle. So the radius is 2*sqrt(2). Now that we know the radius we can determine the area of the circle:
(2*sqrt(2))^2 * pie
2^2 * (sqrt(2))^2 * pie
4 * 2 * pie
8 pie
Correct Answer: [spoiler](A)[/spoiler]
PS: If you are having a hard time with triangles you can get some help from the top 7 triangle tricks https://www.beatthegmat.com/mba/2009/10/ ... art-1-of-7. Hope it helps!!!
Knowing this we can determine that the diagonal of the square is 4*sqrt(2) which is the Diameter of the circle. So the radius is 2*sqrt(2). Now that we know the radius we can determine the area of the circle:
(2*sqrt(2))^2 * pie
2^2 * (sqrt(2))^2 * pie
4 * 2 * pie
8 pie
Correct Answer: [spoiler](A)[/spoiler]
PS: If you are having a hard time with triangles you can get some help from the top 7 triangle tricks https://www.beatthegmat.com/mba/2009/10/ ... art-1-of-7. Hope it helps!!!
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Deepthi Subbu
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MAAJ
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No problemDeepthi Subbu wrote:Thanks a lot for the link on triangle tricks . That really helped
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