Question 70253
Bobby and Ricky are in a 10 lap race on a 1-mile oval track. Bobby averaging 90mph, has completed 2 laps just as Ricky gets his car on the track. What speed does rick have to average to be even with Bobby at the end of the 10th lap.
:
We can simplify this by saying what speed will Ricky have to go to cover 10 mi
while Bobby covers 8 miles?
:
Let s = Ricky's speed
T = dist/speed
:
8/90 = 10/s
Cross multiply
8s = 900
s = 900/8
s = 112.5 mph to overtake Bobby on completion of the 10th lap