<PRE><B>Question 810347</B>
s = d / t
t = d / s
d = s * t
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speed is relative, so firstly consider the closure rate of the two trains:
80 mph
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time to cover 550 miles at 80 mph:
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t = 550 / 80 = 6.875 hours
the trains will meet after t time has passed
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the meeting:
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train a will have traveled:
d = 35 miles/hour * 6.875 hours = 240.625 miles
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train b will have traveled:
d = 45 miles/hour * 6.875 hours = 309.375 miles
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check:
240.625 + 309.375 = 550 
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