Question 33096
Bobby has 8 laps to travel: 8 miles going at 90mph. How long will he take to finish?


speed = distance/time
90 = 8/t
90t = 8
t = 8/90


No point working this out yet... it is a recurring decimal, so do not round it. Leave it as a fraction.


So, Rick comes onto the track. He has 10 laps to do ie 10 miles in the same time, to finish equal with Bobby.


So, speed = distance/time
speed = 10/(8/90)
speed = 900/8
speed = 112.5mph


jon.