Which of the following MUST be true?

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Which of the following MUST be true?

by mkbigmoz » Tue Mar 31, 2009 2:14 pm
My question follows the spoiler. I can't seem to copy properly so the question is supposed to read: -6 is less than or equal to n, which is less than or equal to 10


If it is true that -6 n 10, which of the following must be true?


A n < 8
B n = -6
C n > -8
D -10 < n < 7
E none of the above


[spoiler]Correct Choice: (C)
We should start with answer choice (D) and move up the choices to see which one MUST be true. Choice (D) may be true, but if 7 n 10, then this statement is not true. Choice (C) must be true because all possible values of n specified by the inequality in the question stem are greater than -8. This is the correct choice. We can stop here. Choice (B) is incorrect because there are more values within the range in the question stem than just -6. Choice (A) may be true, but does not have to be. If 8 n 10, choice (A) is not true.

C states that N must be greater than (-8). If this is true, then N can be (-7), but -7 is greater than -6. This would violate the stem. What am I overlooking? Thanks [/spoiler]
Source: — Problem Solving |

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by satish.nagdev » Tue Mar 31, 2009 10:48 pm
you are missing basic principle, in negative numbers value of a large number is less than value of small number
i.e. in this case -7 < -6 hence choice C is correct

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by vittalgmat » Tue Mar 31, 2009 11:56 pm
Set HTML option to OFF in your profile.
Then u can get < and > without interpretation.

HT helps
-V