shasadou wrote:
A migrating bird flew across a lake at an average speed of 18 meters per second. Was the distance that the bird flew across the lake less than 21 kilometers? (1 kilometer = 1000 meters)
(1) It took the bird less than 20 minutes to fly across the lake.
(2) It took the bird less than 0.4 hour to fly across the lake.
Determine the number of minutes required to travel 21 kilometers at the given rate of 18 meters per second:
\(\frac{21-kilometers}{1} * \frac{1000-meters}{1-kilometer} * \frac{1-second}{18-meters} * \frac{1-minute}{60-seconds} ≈ 19.5\) minutes
Since 21 kilometers can be traveled in approximately 19.5 minutes, the distance will be LESS than 21 kilometers if the time is LESS than approximately 19.5 minutes.
Question stem, rephrased:
Was the time less than approximately 19.5 minutes?In Statement 1, the time is less than 20 minutes.
In Statement 2, the time is less than 24 minutes.
When the statements are combined, the time can be 19 minutes (in which case the answer to the rephrased question stem is YES) or 19.9 minutes (in which case the answer is NO).
INSUFFICIENT.
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