GMATprep PS question

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by AleksandrM » Tue Jul 01, 2008 9:16 am
The sum of every two sides of a triangle must be greater than the third side.



Answer is None.

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by somail » Tue Jul 01, 2008 3:38 pm
Hi, here is how I would solve it:

1. first find the missing value for each perimeter listed under options I-III.

I. 2+5+2=9 (2 is the missing leg)
II. 2+5+8=15 (8 is the missing leg)
III. 2+5+12=19 (12 is the missing leg)

2. Find which options could be a valid triangle based on the rule that the sum of the two shorter sides must be greater than the longest side.

I. 2+2>5 Not Valid
II. 2+5>8 Not Valid
III. 2+5>12 Not Valid

Assuming I am thinking straight, the answer is "None"

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by Sunny22uk » Tue Jul 01, 2008 5:13 pm
Answer is indeed "none".

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by mlane25269 » Tue Jul 01, 2008 5:13 pm
Could I have also used this rule...

Third side is greater than the difference of the other two sides or less than the sum of the other two sides.

So 3 < x < 7
because 5-2 <x> x

and since none of the answers choices are between 3 and 7 then the answer would be "None" right?