Question 50640
Bobby and Rick are in a 10 lap race on a one-mile track oval track. Bobby, averaging 90 mph, has completed two laps just as Rick is getting his car onto the track. What speed does Rick have to average to be even with Bobby at the end of the tenth lap?
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Bobby DATA:
rate=90 mph ; distance = 8 miles ; time= d/r=8/90 hrs.

Rick DATA:
rate=x mph ; distance = 10 miles ; time = d/r= 10/x

EQUATION:
time Rick = time Bobby
10/x= 8/90

x=900/8
x=112.5 mph (Rick's rate)

Cheers,
Stan H.