Question 715132: I need help with this word problem.
Two cars are in the same parking lot. The first car leaves the lot at 1:00pm and travels at an average speed of 40 mph down a highway. An hour later, at 2:00pm the second car leaves and travels at an average speed of 50 mph in the same direction on the same road. How many hours will the second car have to drive to catch up to the first car?
Answer by ankor@dixie-net.com(22740)   (Show Source):
You can put this solution on YOUR website! Two cars are in the same parking lot.
The first car leaves the lot at 1:00pm and travels at an average speed of 40 mph down a highway.
An hour later, at 2:00pm the second car leaves and travels at an average speed of 50 mph in the same direction on the same road.
How many hours will the second car have to drive to catch up to the first car?
:
Let t = travel time of the 2nd car to catch the first
then
(t+1) = travel time of the 1st car, when it is caught (left an hour earlier)
:
When this happens, both cars will have traveled the same distance.
Write a distance equation; dist = speed * time
:
2nd car dist = 1st car dist
50t = 40(t+1)
50t = 40t + 40
50t - 40t = 40
10t = 40
t = 40/10
t = 4 hrs for the 2nd car to catch the 1st
:
That's pretty easy, isn't it?
:
Check this by finding the actual dist each car traveled
50(4) = 200 mi
40(5) = 200 mi
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