GRE Practice Test

Answers and Explanations

1. The correct answer is (A).  Sentence completions are meant to test your intuitive grasp of the structure and logic of sentences. Keywords usually indicate either opposition or similarity. That is, the keyword will indicate that the missing word is either opposite or like another word in the sentence.  In this example, the keyword unless indicates opposition: in this case, opposition to continuing in the race. The unless tells us that unless something good happens to her performance, she’ll go in the opposite direction. That is, she’ll withdraw from the race. Because we know her campaigners are devoted, we can imagine that they would feel consternation at her withdrawing. Therefore, the answer is (A). You might have been tempted by (B), but “abstain from” isn’t quite right, as it would indicate that she isn’t in the race already.

2. The correct answer is (B). This is an example of a problem-solving question.  For every 4 guppies there are 5 angelfish: it’s a ratio.  Since there can’t be a fraction of a fish, the total number of angelfish and guppies must be an integer multiple of 9.  For every 9 fish, there is 1 more guppies than angelfish.  Since you are given that there are 20 more guppies than angelfish in the whole aquarium, the total number of guppies and angelfish is equal to 20 times 9 = 180.

3. The correct answer is (C).  This is an example of a logical reasoning question. Questions that ask you to find an unstated premise, or assumption, are testing your ability to fill in missing steps in an argument.  If you get stuck on a question like this, use the denial test: Negate each answer choice as you read it. The correct answer, when it’s been negated, will turn the argument into gibberish. The negation of the correct answer must be inconsistent with the argument.  Here, the answer is (C). Let’s try negating (C). Let’s pretend that Susan DOESN’T obey her company’s regulations. Then the company’s regulations would have no effect on her, and we’d have no reason to believe that she doesn’t smoke in the cafeteria. That is, the author’s evidence about the company’s regulations wouldn’t add up to the conclusion that “Susan does not smoke in the cafeteria.”