= TT (2rs + s^2)
= TTs(2r -s)
hence E is the answer.
Skywalker wrote:Please find the sum uploaded as an image...I am not able to get the answer which is option 5.
GMAT Prep : Geometry
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ashokkadam
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area of metal frame = TT * (r+s)^2 - TT * r^2
= TT (2rs + s^2)
= TTs(2r -s)
hence E is the answer.
= TT (2rs + s^2)
= TTs(2r -s)
hence E is the answer.
Force and mind are opposites; morality ends where a gun begins.
ashokkadam wrote:area of metal frame = TT * (r+s)^2 - TT * r^2
= TT (2rs + s^2)
= TTs(2r -s)
hence E is the answer.
Skywalker wrote:Please find the sum uploaded as an image...I am not able to get the answer which is option 5.
It has to be TTs(2r+s) from ur calculation
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ashokkadam
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Right! there was a typo. But the final answer is correct and that is what I meant.
anyways i have corrected below
anyways i have corrected below
narik11 wrote:ashokkadam wrote:area of metal frame = TT * (r+s)^2 - TT * r^2
= TT (2rs - s^2)
= TTs(2r -s)
hence E is the answer.
Skywalker wrote:Please find the sum uploaded as an image...I am not able to get the answer which is option 5.
It has to be TTs(2r+s) from ur calculation
Force and mind are opposites; morality ends where a gun begins.
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GMATGuruNY
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The figure shows the top side of a circular medallion made of a circular piece of colored glass surrounded by a metal frame represented by the shaded region. If the radius of the medallion is r and the width of the metal frame is s, what is the area of the metal frame in terms of r and s?
1. pi (r-s)^2
2. pi (r^2 -s^2)
3. 2pi(r-s)
4. pi*r*(2r-s)
5. pi*s*(2r-s)
Since there are variables in the answer choices, we can plug in values.
Let r = 3.
Then area of medallion = 9pi.
Let s = 1.
Then radius of glass = r-s = 3-1 = 2.
Area of glass = 4pi.
Area of frame = 9pi - 4pi = 5pi. This is our target answer.
Only answer choice E works:
pi*s*(2r-s) = pi*1*(2*3 - 1) = 5pi.
The correct answer is E.
1. pi (r-s)^2
2. pi (r^2 -s^2)
3. 2pi(r-s)
4. pi*r*(2r-s)
5. pi*s*(2r-s)
Since there are variables in the answer choices, we can plug in values.
Let r = 3.
Then area of medallion = 9pi.
Let s = 1.
Then radius of glass = r-s = 3-1 = 2.
Area of glass = 4pi.
Area of frame = 9pi - 4pi = 5pi. This is our target answer.
Only answer choice E works:
pi*s*(2r-s) = pi*1*(2*3 - 1) = 5pi.
The correct answer is E.
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Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
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