What is the perimeter...

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What is the perimeter...

by BTGmoderatorLU » Tue Oct 17, 2017 6:53 pm
What is the perimeter of a square with area 9p^2/16 ?

A. 3p/4
B. 3p^2/4
C. 3p
D. 3p^2
E. 4p/3

The OA is C.

Can any expert illustrate this with an example please? I don't have it so clear.

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Answer

by EconomistGMATTutor » Tue Oct 17, 2017 7:22 pm
Hello LUANDATO.

Let's take a look at your question.

The area of a square is equal to L² where L is the lenght of the side of the square.

So, we have $$L^2=\frac{9P^2}{16},$$

this implies that $$L=\frac{3P}{4}.$$

Now, the perimeter of a square is 4L. It is, $$Perimeter=4L=4\cdot\frac{3P}{4}=3P.$$

So, the correct asnwer is C.

I hope this answer can help you.

Example:

Let be P=2, so the area of the square is A=9*4/16.

It implies that the side of the square is equal to 3*2/4. Now, the perimeter is 4*(3*2/4)=3*2.

On the other hand, 3*2=3*P.

I'm available if you'd like any follow up.
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by BTGmoderatorLU » Wed Oct 18, 2017 9:20 am
Thank you so much for your help! Now, it's so clear to me! Great, I'll have on mind!

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by [email protected] » Wed Oct 18, 2017 8:28 pm
Hi LUANDATO,

We're told that the area of a SQUARE is (9P^2)/16. We're asked for the PERIMETER of the square. This question can be solved by TESTing VALUES.

Since the denominator is 16, we can 'cancel' it out if we make P=4...

IF... P=4, then the area of the square is 9(16)/16 = 9. This means that each side of the square = 3. Thus, we're looking for an answer that equals 4(3) = 12 when we plug P=4 into the answer choices. There's only one answer that matches...

Final Answer: C

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Re: What is the perimeter...

by Scott@TargetTestPrep » Sun Feb 02, 2020 11:30 am
BTGmoderatorLU wrote:
Tue Oct 17, 2017 6:53 pm
What is the perimeter of a square with area 9p^2/16 ?

A. 3p/4
B. 3p^2/4
C. 3p
D. 3p^2
E. 4p/3

The OA is C.

Can any expert illustrate this with an example please? I don't have it so clear.
Each side of the square is 3p/4, so the perimeter of the square is 3p/4 * 4 = 3p.

Answer: C

Scott Woodbury-Stewart
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