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What is the perimeter of quadrilateral Q?

Expert replies
Source: — Data Sufficiency |

BTGmoderatorDC wrote:What is the perimeter of quadrilateral Q?

(1) Q is a rectangle.
(2) The area of Q is 25.
Target question: What is the perimeter of quadrilateral Q?

If we recognize that each statement alone is not sufficient, we can jump straight to......

Statements 1 and 2 combined
There are several quadrilaterals that satisfy BOTH statements. Here are two:
Case a: rectangle Q has dimensions 1 x 25 (this means its area is 25). In this case, the answer to the target question is the perimeter = 1 + 1 + 25 + 25 = 53
Case b: rectangle Q has dimensions 5 x 5 (this means its area is 25). In this case, the answer to the target question is the perimeter = 5 + 5 + 5 + 5 = 20
Since we cannot answer the target question with certainty, the combined statements are NOT SUFFICIENT

Aside: hold on Brent! Statement 1 says that quadrilateral Q is a rectangle, but in case b, you gave the dimensions of a square .
Great observation, but a square is a type of rectangle. . . . . . . . mind blown <i class="em em-scream_cat"></i>!!!!

Answer: E

Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
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