SOLUTION: A truck enters a highway driving 60 mph. A car enters the highway at the same place 7 minutes later and drives 72 mph in the same direction. From the time the car enters the hig

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Question 208301: A truck enters a highway driving 60 mph. A car enters the highway at the same place 7 minutes later and drives 72 mph in the same direction.
From the time the car enters the highway, how long will it take the car to pass the truck?

Found 2 solutions by Alan3354, rfer:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
A truck enters a highway driving 60 mph. A car enters the highway at the same place 7 minutes later and drives 72 mph in the same direction.
From the time the car enters the highway, how long will it take the car to pass the truck?
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60 mph is 1 mile per minute, so the truck is 7 miles ahead when the car enter.
The car is gaining on the truck 1t 12 mph (72-60).
7 miles at 12 mph will take 35 minutes.

Answer by rfer(16322) About Me  (Show Source):
You can put this solution on YOUR website!
The car gains distance at 12 mph
The truck is 7.2 miles ahead of the car
7.2/12=0.6 hr or 36 min