9 hours long after the second runner started will the second runner overtake the first runner.
What does it mean to do speed?
Runner I = 6 mph
Runner II = 7 mph
Difference in time= 90 minutes
Train A will have covered 9 miles before Runner II starts
catch up distance= 9 miles
catch up speed = 7-6 mph
catch up speed = 1 mph
Catchup time = catchup distance/catch up speed
catch up time= 9/1
catch up time= 9 hours
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