SOLUTION: Two executives in cities 400 miles apart drive to a business meeting at a location on the line between their cities. They met after 4 hours. Find the speed of each car if one trave
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Question 485924: Two executives in cities 400 miles apart drive to a business meeting at a location on the line between their cities. They met after 4 hours. Find the speed of each car if one travels 20 miles per hour faster than the other. Answer by htmentor(1343) (Show Source):
You can put this solution on YOUR website! Two executives in cities 400 miles apart drive to a business meeting at a location on the line between their cities. They met after 4 hours. Find the speed of each car if one travels 20 miles per hour faster than the other.
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Let d = the distance traveled by the slower car
Then the distance traveled by the faster car = 400-d
Let v = the speed of the slower car
Then v+20 = the speed of the faster car
Since speed = distance/time, and the time is 4 hrs, we can write the following 2 equations:
v = d/4 [1]
v+20 = (400-d)/4 [2]
Solve for d in [1] and substitute into [2]:
v+20 = (400-4v)/4
v+20 = 100-v
2v = 80
v = 40 mph
Therefore, the faster car's speed = 60 mph
