tonebeeze wrote:
Of the numbers q, r, s, and t, which is greatest?
(1) The average (arithmetic mean) of q and r is s.
(2) The sum of q and r is t.
Target question: Of the numbers q, r, s, and t, which is greatest? Statement 1: The average (arithmetic mean) of q and r is s No information is given about t
Statement 1 is NOT SUFFICIENT
Statement 2: The sum of q and r is t.No information is given about s
Statement 2 is NOT SUFFICIENT
Statements 1 and 2 combined Statement 1 tells us that (q + r)/2 = s
Multiply both sides by 2 to get:
q + r = 2sStatement 2 tells us that
q + r = tThere are several values of q, r, s and t that satisfy BOTH statements. Here are two:
Case a: q = -1, r = 1, s = 0 and t = 0. In this case, the answer to the target question is
r is the greatest valueCase b: q = 1, r = -1, s = 0 and t = 0. In this case, the answer to the target question is
q is the greatest valueSince we cannot answer the
target question with certainty, the combined statements are NOT SUFFICIENT
Answer: E
Cheers,
Brent
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