zion wrote:

A local department store hires college students for one month every spring to audit its unsold inventory. It costs the department store 20 percent less to pay wages to students than it would cost to hire outise auditors from a temporary service. Even after factoring the cost of training and insuring the students against work-related injury, the department store spends less money by hiring the student auditors than it would by hiring from the temporary service.

The statement above, if true, best support which of the following assertions?

A) The amount spent on insurance for college student auditor is more than 20 percent of the cost of paying the college student's basic wages.

B) It takes 20 percent less time for the college student to audit the unsold inventory than it does for the outside auditors.

C) The department store pays its college student auditors 20 percent less than the temporary service pays its auditors

D) By hiring college students, the department store will cause 20 percent of the auditors at the temporary service to lose their jobs.

E) The cost of traning its own college student auditors is less than 20 percent of the cost of hiring auditors from the temporary services.

KAPLAN OFFICIAL EXPLANATION:

We don't have to look too deeply into this one to determine that it falls squarely into the numbers and statistics realm. All we have is evidence, and the first piece presents a statistical claim: The department store pays college students 20 percent less than it would pay employees from a temporary service. Next comes the numerical claim: Add the costs of training and insurance, and the store still pays less for college students. The correct answer must arise from the facts: college students cost the store up to 20 percent less than do employees from a temporary service—even after training and insurance. Prephrasing an answer would be tough, so we should move right to testing the choices.

An 800 test taker has an intuitive sense of when to try to prephrase answers and when to simply use a solid understanding of the given information to test the choices. In either case, he attacks the choices aggressively.

(A) attempts to relate the amount spent on insurance for student auditors to the total amount of their wages, but we have no basis for which to make this comparison. The amount spent on insurance for college-student auditors can be more, less, or equal to 20 percent of their basic wages without violating the numerical facts presented.

(B) and (D) should have been fairly easy kills. (B) involves time, a subject not included in the stimulus, while (D) mentions the loss of jobs at the temporary service, even though we know nothing about the overall demand for their auditors.

(С) is a little more subtle, but it involves how much the temporary service pays its auditors, not how much it charges the store for them. A classic "scope shift," in fact—and a pretty good premonition of things to come.

An 800 test taker always pays attention to the scope of the argument; this helps him to axe easy and more difficult choices alike.

(E) fits, and one way we can verify that it's correct is to see what happens it it's not true. If the cost of training college students is more than 20 percent of the cost of hiring auditors from the temporary service, the overall cost of college students must be higher than the cost of temporary-service auditors. That would contradict the stimulus, so (E) must be true.

An 800 test taker has many tricks up her sleeve. She knows that one way to verify an answer in an Assumption or Inference question is to see what happens when she denies or negates the choice. If doing so makes the argument fall apart, then she knows she's found the winner.

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