GMAT Official Guide 2019 If the circumference of a

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by Brent@GMATPrepNow » Sun Jul 01, 2018 6:42 pm
BTGmoderatorDC wrote:If the circumference of a circle inscribed in a square is 25Ï€, what is the perimeter of the square?


A. 20

B. 25

C. 40

D. 50

E. 100
We have the following:
Image

The perimeter of the circle = 25Ï€

We can see that the perimeter of the square is GREATER THAN the perimeter of the circle

25π ≈ (25)(3) ≈ 75
So, the perimeter of the square is GREATER THAN 25Ï€

Check the answer choices....only one answer choice works.

Answer: E

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by Brent@GMATPrepNow » Sun Jul 01, 2018 6:42 pm
BTGmoderatorDC wrote:If the circumference of a circle inscribed in a square is 25Ï€, what is the perimeter of the square?


A. 20

B. 25

C. 40

D. 50

E. 100
We have the following:
Image

The perimeter of the circle = 25Ï€

We can see that the perimeter of the square is GREATER THAN the perimeter of the circle

25π ≈ (25)(3) ≈ 75
So, the perimeter of the square is GREATER THAN 25Ï€

Check the answer choices....only one answer choice works.

Answer: E

Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
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by Shahrukh_mbabreakspace » Mon Jul 02, 2018 5:24 am
If circle is inscribed in a square then diameter of the square is same as the side of the square.

So we know 2 $$\pi$$ r= 25 $$\pi$$
so it means d= 2r= 25

So perimeter of square will be 25 * 4= 100

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by Scott@TargetTestPrep » Wed Jul 04, 2018 6:09 pm
BTGmoderatorDC wrote:If the circumference of a circle inscribed in a square is 25Ï€, what is the perimeter of the square?


A. 20

B. 25

C. 40

D. 50

E. 100
When a circle is inscribed in a square, the diameter of the circle is equal to the side of the square.

Since circumference = πd, we have:

Ï€d = 25Ï€

d = 25 = side of the square

Thus, the perimeter of the square is 25 x 4 = 100.

Answer: E

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The perimeter of the circle = 25π

2πr = 25π
So r= 25/2 so Diameter = 2* 25/2 = 25

So the perimeter of the square = 4a = 4* 25 = 100