Zarrolou and Mau5 have great posts. However, I also want to analyze the question in other way by plugging in number. Hope it helps.
First of all, to solve the “flaw of reasoning”, you must think about the structure of the argument before examining the answer choices.The structure of this argument is:
MW sales Manager: I’m unhappy to say our office will not lead the company in sales this quarter
Executive: South sales office had a strong performance this quarter, because they improved sales from 10% to 25%
What the Executive means? He applauded the South office, his reasoning is based on “percentage” data to conclude the performance.
This is one of the most frequent traps in GMAT CR, so always keep your eyes on this.ANALYZE EACH ANSWER:
(A) does not address the reasons why the ACME Midwest Sales Office had a bad quarter.Wrong.
Out of scope. The executive does not mention the reasons of weak sales of MW office. Keep in mind, in "flaw of reasoning", new information is NOT accepted. Just use information in the stimulus.
(B) neglects the possibility that overall sales have increased dramatically.Wrong. TEMPTING. But it’s wrong.
Because if overall sales increased, and South office’s sales improved from 10% to 25% Definitely can say the South office’s performance was as good as the Executive said ==> No flaw here.
(C) assumes an increase in sales percentage resulted from increased performance.Correct. Improvement of percentage does not always mean improvement in performance
.For example: Before:
Total company sales = 100. South office accounted for 10% => Its sales = 10After:
Total company sales = 30. South office accounted for 25% => Its sales = 7.5
Clearly, 25% improvement does not mean anything.
(D) uses percentage data when he should be using absolute number data.Wrong. Tempting. But it’s wrong,
because it is NOT the flaw of this argument. If the total sales
of the company increased
==> the use of “percentage” is a good measure
(E) neglects to consider other sales offices.Wrong.
Clearly out of scope. The argument just focuses on the South office’s
performance and its improvement in sales percentage.
Hope it's clear.
Please +1 KUDO if my post helps. Thank you.
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