Question 980571: Two trains are 500 miles apart when they first start moving towards each other. If in two hours the distance between them is 300 miles, and one train goes 20 miles faster than the other, find the speed of the faster train. I think my teacher said there are two solutions for this problem.
Answer by josgarithmetic(39620)   (Show Source):
You can put this solution on YOUR website! The two trains moving toward each other are approaching at the sum of their individual rates.
RT=D relates rate, time, distance.
r, the speed or rate of the slower train.
Slow train, r
Fast train, r+20
time, 2 hours
distance covered, 500-300=200
If this equation makes sense to you, then just simple arithmetic should be apparent for how to solve for r.
ONE SOLUTION for r;
not two solutions.
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Your teacher would have meant that if the FASTER train goes at speed of r, then the SLOWER train goes at the speed of r-20. The result for rates of fast and slow trains will still be the same as if you assigned r to the slow train and r+20 to the fast train.
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