Question 1112437: Two trains leave the station at the same time, one heading west and the other east. The westbound train travels 20miles per hour faster than the eastboundtrain. If the two trains are 600miles apart after 4hours, what is the rate of the westbound train?
Found 3 solutions by josgarithmetic, ikleyn, MathTherapy:
Answer by josgarithmetic(39799)   (Show Source):
Answer by ikleyn(53763)  (Show Source):
You can put this solution on YOUR website! .
Let "r" be the rate of the slower train, in miles per hour.
Then the rate of the faster train is (r+20) mph.
The distance covered by the slower train in 4 hours is 4r miles.
The distance covered by the faster train in 4 hours is 4*(r+20) miles.
Since the trains move in opposite directions, the distance between them is the sum of the two distances above.
It gives you an equation
4r + 4*(r+20) = 600.
Simplify and solve for "r":
4r + 4r + 80 = 600
8r = 600 - 80 = 520
r =  = 65.
Answer. The rate of the slower train is 65 mph. The rate of the faster train is 65+20 = 85 mph.
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Be aware: the solution by @josgarithmetic is W R O N G and I R R E L E V A N T.
For your safety, simply ignore it.
Answer by MathTherapy(10810)  (Show Source):
You can put this solution on YOUR website!
Two trains leave the station at the same time, one heading west and the other east. The westbound train travels 20miles per hour faster than the eastboundtrain. If the two trains are 600miles apart after 4hours, what is the rate of the westbound train?
East and west form a STRAIGHT LINE, not a triangle, so as usual, IGNORE the person who continues to post RUBBISH!!
Let speed of westbound train be S
Then speed of eastbound train = S – 20
We then get: 4S + 4(S – 20) = 600
4S + 4S – 80 = 600
8S = 680
S, or speed of westbound train = 
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