SOLUTION: A train leaves philadelphia at 5:00 PM. A second train leaves the same city in the same direction at7:00 PM. The second train travels 30 mph faster than the first. If the second tr

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Question 1066676: A train leaves philadelphia at 5:00 PM. A second train leaves the same city in the same direction at7:00 PM. The second train travels 30 mph faster than the first. If the second train overtakes the first at 11:00 PM. What is the speed of the two trains.
Answer by josgarithmetic(39623) About Me  (Show Source):
You can put this solution on YOUR website!
Use time quantities instead of points in time.
        SPEED         TIME        DISTANCE

SLOW       r           4+2=6        d

FAST      r+30         4            d


system%28%28r%29%286%29=d%2C%28r%2B30%29%284%29=d%29

The distances, each d, is the same.

6r=4%28r%2B30%29
Solve for r.