inequality problem.

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by Gurpinder » Sun Aug 22, 2010 5:23 pm
Taniuca wrote:Which of the following CANNOT be the value of ab if and -12<=a<=-7 and b>8?

-200
-112
-96
-72
-56
-12<=a<=-7 and b>8?

so a = -12,-11,-10,-9,-8,-7
b > 8 ---> so b = 9,10,11,12.....

The answer is -56

56=7x8 --> we have the -7 as A but we dont have 8 from B.
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by srajan » Sun Aug 22, 2010 10:09 pm
Gurpinder wrote:
Taniuca wrote:Which of the following CANNOT be the value of ab if and -12<=a<=-7 and b>8?

-200
-112
-96
-72
-56
-12<=a<=-7 and b>8?

so a = -12,-11,-10,-9,-8,-7
b > 8 ---> so b = 9,10,11,12.....

The answer is -56

56=7x8 --> we have the -7 as A but we dont have 8 from B.
Gurpinder is right in his answer. However, it is wrong to assume that a and b are integers until unless it is not mentioned in the question.

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by Gurpinder » Mon Aug 23, 2010 4:41 am
The only reason i assumed it to be integers because all the answer choices were integers. Int x int = int.
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by Tani » Mon Aug 23, 2010 8:21 am
Never assume integers on the GMAT it's one of their favorite traps! :)
Tani Wolff