rags wrote:

Mary passed a certain gas station on a highway while traveling west at a constant speed of 50 miles per hour. Then, 15 minutes later, Paul passed the same gas station while traveling west at a constant speed of 60 miles per hour. If both drivers maintained their speeds and both remained on the highway for at least 2 hours, how long after he passed the gas station did Paul catch up with Mary?

A. 30 min

B. 45 min

C. 1 hr

D. 1 hr 15 min

E. 1 hr 30 min

after 15 minutes as paul is passing the gas station, Mast will be 50 *15/60 = 12.5 miles away

relative speed since they are moving in same direction will be 60 - 50 =10 mph

time taken to cover 12.5 miles = 12.5/10 = 1.25 hours = 1 hour 15 minute

Option D

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