SOLUTION: A container ship left thr Dania Pier and traveled north. An aircraft carrier left four hours later traveling at 30 mph in an effort to catch up to the container ship. After traveli
Question 505940: A container ship left thr Dania Pier and traveled north. An aircraft carrier left four hours later traveling at 30 mph in an effort to catch up to the container ship. After traveling for eight hours the aircraft carrier finally caught up. What was the container ships average speed? Found 2 solutions by stanbon, solver91311:Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! A container ship left thr Dania Pier and traveled north. An aircraft carrier left four hours later traveling at 30 mph in an effort to catch up to the container ship. After traveling for eight hours the aircraft carrier finally caught up. What was the container ships average speed?
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Container ship DATA:
time = 12 hrs ; rate = r mph ; distance = rt = 12r miles
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Aircraft carrier DATA:
time = 8 hrs ; rate 30 mph ; distance = rt = 240 miles
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Equation:
distance = distance
12r = 240
r = 20 mph (container ship rate)
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Cheers,
Stan H.
The aircraft carrier was underway at 30 knots for 8 hours. Presuming still water for the entire time, the aircraft carrier advanced 240 nautical miles. Since we are concerned with the moment in time when the aircraft carrier overtook the container ship, the container ship, at that moment, must have advanced the same distance. But the container ship was underway for a total of 12 hours (the 4 hour head start plus the 8 hours the aircraft carrier was underway leading up to the moment of interception). Average speed is given by distance travelled divided by the total time.
By the way, remind whomever wrote this problem that ships' speeds are measured in nautical miles per hour (knots). A staute mile (land mile) is 1760 yards. A nautical mile is approximately 2025 yards. Hence knots are about 12.5% faster than miles per hour.
John
My calculator said it, I believe it, that settles it
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