1. ## rxt=d

Bobby and Rick are in a 10-lap race on a one mile oval track. Bobby averaging 90mph, 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? *Hint: Bobby does 8 miles in the same time as Rick does 10 miles.
I am lost

Bobby and Rick are in a 10-lap race on a one mile oval track. Bobby averaging 90mph, 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? *Hint: Bobby does 8 miles in the same time as Rick does 10 miles.
I am lost
A way to work it.
The track is 1 mile in length.
At 90 mph how many laps (it's a 1 mile track) will Bobby make in 1 hour?
You should say 90.
If he only drives for 1/2 hour, how many miles?
If he drives for 1/10 of an hour, how many miles?

At 90 mph how long will it take Bobby to make 1 lap around the track? <-- key question.

How long will it take Bobby to make 2 laps around the track? <-- IMPORTANT ANSWER

How long will it take Bobby to make 10 laps around the track? <-- Bobby's TOTAL time on the course.

Rick will be on the track for how long.
Since he will complete the course the same time as bobby, Rick's time must be T3-T2.
Call that time t

Distance = Rate x Time
Bobby's speed
10 miles = Z mph x t hours
(omitting the units of measure)

$\displaystyle 10 = z \times t$

$\displaystyle \dfrac{10}{t} = z$

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