Question 1041720: Using Distance + Rate * Time. Two trucks leave warehouses that are 540 miles apart traveling toward one another. They meet 4 hours late. The first truck was traveling 15 mph slower than the second truck. How fast was each truck traveling?
Answer by Boreal(15235)   (Show Source):
You can put this solution on YOUR website! The total distance is 540 miles
speed of first truck is x mph and he drives 4 hours so distance is 4x miles
speed of second truck is (x+15) mph, and he drives 4 hours, so distance is 4x+60 miles. Note, first truck is driving slower than the second truck; one could use (x-15) for first truck and x for the second.
4x+4x+60=540
8x+60=540
subtract 60 from both sides
8x=480
divide both sides by 8
x=60 mph, first truck
(x+15)=75 mph, second truck
In 4 hours, the first truck travels 60*4=240 miles
the second truck travels 75*4=300 miles
That is 540 miles
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