Data InsightsMulti-Source Reasoning

Free GMAT Multi-Source Reasoning Practice Question

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Thornfield Apiary keeps bees at two sites, a Meadow site and a Ridge site. After the season the beekeeper wrote: our average hive produced 54 pounds of honey this year. The Meadow hives averaged 60 pounds and the Ridge hives averaged 40 pounds, so 54 is right where I'd expect the apiary's average to land, about midway. These three figures, the Meadow site mean of 60 pounds, the Ridge site mean of 40 pounds, and the claimed apiary mean of 54 pounds, are the only per-hive averages recorded for the season. The cooperative that buys Thornfield's honey wants a verified per-hive average across the whole apiary to set a bulk price.

The cooperative is checking the beekeeper's reasoning about the apiary average. For each statement, select Yes if it is accurate given the sources; otherwise select No.

Statement 1: The apiary-wide per-hive average (54 lb) is closer to the Meadow site mean than to the Ridge site mean. Statement 2: The apiary-wide average sits closer to Meadow's mean because Meadow has more hives than Ridge. Statement 3: The simple average of the two site means equals the apiary-wide per-hive average.

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Answer & Explanation

Correct answer

1: Yes · 2: Yes · 3: No

Statement 1: from the study summary the apiary mean is 54, Meadow's mean is 60, and Ridge's is 40; the gap to Meadow (6) is smaller than the gap to Ridge (14), so 54 is closer to Meadow. Yes.

Statement 2: the results table shows Meadow at 35 hives and Ridge at 15, which are unequal, so by the methodology note the weighted apiary average is pulled toward the larger Meadow site. Yes.

Statement 3: the simple average of the two site means from the study summary is (60 + 40) ÷ 2 = 50, but the apiary-wide per-hive average is 54; they are not equal. The simple average equals the weighted average only with equal hive counts, which the results table denies. No.