Is the perimeter of a certain triangle less than 24 inches?

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Sat Mar 07, 2020 5:36 pm
Princeton Review

Is the perimeter of a certain triangle less than 24 inches?

1) The shortest side of the triangle is 8 1/4 inches.
2) The triangle is isosceles and the longest side is 1 inch longer than each of the other sides.

OA A
Target question: Is the perimeter of a certain triangle less than 24 inches?

Statement 1: The shortest side of the triangle is 8[m][fraction]1/4[/fraction][/m] inches.
This tells us that the other two sides must have lengths that are AT LEAST 8.25 inches
8.25 + 8.25 + 8.25 = 24.75, so the minimum possible perimeter is 24.75 inches
The answer to the target question is NO, the perimeter is not less than 24 inches
Since we can answer the target question with certainty, statement 1 is SUFFICIENT

Statement 2: The triangle is isosceles and the longest side is 1 inch longer than each of the other sides.
There are several possible cases that satisfy statement 2. Here are two:
Case a: The three lengths are 3,3,4. Here, the perimeter = 3 + 3 + 4 = 10. So, the answer to the target question is YES, the perimeter is less than 24 inches
Case b: The three lengths are 13,13,14. Here, the perimeter = 13 + 13 + 14 = 40. So, the answer to the target question is NO, the perimeter is not less than 24 inches
Since we cannot answer the target question with certainty, statement 2 is NOT SUFFICIENT

Answer: A

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Brent
Brent Hanneson - Creator of GMATPrepNow.com
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