Problem Solving

Note: This problem is not representative of GMAT questions, but the strategy for eliminating answers is relevant to solving GMAT questions.

Q. Which of the following must be true?

x > 1
x > 2
x > 3
x > 4
x > 5

How can this question be answered?

Solution

[spoiler]Though this is an extreme example, logic will sometimes eliminate answer choices since only one answer can be correct and one answer has to be correct.

If x is greater than two, then it must also be greater than one. Both answers can't be correct so answer B cannot be correct. The same thing is true of three other answers too--if x is larger than 3, 4, or 5 it is larger than one. C, D, and E cannot be selected without multiple answers being correct. The only answer that doesn't force any other answer also be true is A.

This doesn't mean that the less restrictive answer is always correct, simply that the more restrictive answer cannot be correct.

Additionally, on Roman numeral problems, if one Roman numeral statement is more restrictive than, and inclusive of, another, confirmation of the more restrictive statement confirms the other. Conversely, disqualification of the less restrictive statement also disqualifies the more restrictive statement.[/spoiler]

agreed

What if x is 0.5!