Question 228200: a train leaves town a for town b, traveling at 35 mi/h. at the same time, a second train leaves town b for town a at 45 mi/h. if the towns are 320 miles apart, how long will it take for the two trains to meet? so this is the problem I need to solve. I know d= rt I represented train 1 as x and train 2 as x-10 since it went 10 mi/h slower. added them 2x-10=320 for miles apart came up with 165 miles but question was how long not miles. I am lost as to proper steps
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! a train leaves town a for town b, traveling at 35 mi/h. at the same time, a second train leaves town b for town a at 45 mi/h. if the towns are 320 miles apart, how long will it take for the two trains to meet?
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a to b DATA:
rate = 35 mph ; distance = x miles ; time = d/r = x/35 hrs
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b to a DATA:
rate = 45 mph ; distance = 320-x miles ; time = d/r = (320-x)/45 hrs
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Equation:
time = time
x/35 = (320-x)/45
45x = 35*320-35x
80x = 35*320
x = 140 miles
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time = d/r = 140/35 = 4 hrs (time before the trains meet)
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Another way to work the problem:
The combined rates of the two trains is 35+45 = 80 mph
The time for them together to cover 320 miles is 320/80 = 4 hrs.
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Cheers,
Stan H.
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