While on a summer vacation in Hawaii, Carla goes for an ocean ride on a mystic porpoise named Noelani. If Noelani maintains a constant speed for the entire trip, does the ride take less than 3 hours ?
(1) Noelani swims faster than 6 miles per hour.
(2) The ride is 20 miles in the winter, but is then reduced by a mile per month until the fall.
I don't have the OA.
This is a yes/no question, asking about the ride--is it faster than three hours?
Statement 1) clearly doesn't help to answer that. It gives us a minimum speed, but no distance. A 6mph trip takes 3 hours if it's exactly 18 miles long, so the answer is "Yes" for a 15 mile trip and "No" for a 20 mile one--and that's only if we assume minimum speed, which isn't necessarily the case. Insufficient.
Statement 2), meanwhile, gives no clues about speed. Obviously insufficient.
Put them together, though, and we have a hint. The speed in statement 1 will take less than three hours for a trip of less than 18 miles. And if we assume that Spring, between Winter and Summer, is three months long, then going from some point in the Winter to some point in the Summer, the Noelani's circuit has dropped by a minimum of three hours. A 17 mile-or-shorter trip at 6-or-more mph will definitely take less than 3 hours. We can answer the question "Yes," and that means that Together, choice (C), is the correct answer.
Note, however, that this problem isn't quite test like. I've never seen a GMAT question referencing the time of the seasons; in fact, since some parts of the globe don't have four seasons, the GMAT is very unlikely to require knowledge about it.
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