SOLUTION: a truck dives along the highway at a constant rate of 60 mph, as it passes a rest area. Exactly 9 minutes later, a truck driving 70 mph passes the same rest area. how long will it

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Question 984778: a truck dives along the highway at a constant rate of 60 mph, as it passes a rest area. Exactly 9 minutes later, a truck driving 70 mph passes the same rest area. how long will it take the faster try k to catch up to the slower truck? how far from the rest area will they beat that time?
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Convert the 9 minutes to hours.
T=9%2F60=3%2F20
So if we start the clock when the second truck passes the rest area, the first truck is,
D%5B1%5D=R%2AT=60%2A%283%2F20%29=9mi ahead.
So then,
R%5B1%5D%2At%2B9=R%5B2%5D%2At
60t%2B9=70t
10t=9
t=10%2F9hr
or approximately,
t=%2810%2F9%2960=600%2F9=66%262%2F3min
.
.
.
The distance from the rest area would be,
D=70%2810%2F9%29=700%2F9=77%267%2F9mi