<PRE><B>Question 817157</B>
a = s mph
b = (s + 45) mph
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s = d / t
d = s * t
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when the trains meet at 10 PM they are both at the same distance D from the station, but b has traveled 3 hours less than a 
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train a:
D = a(10 - 3)
D = 7a
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train b:
D = b(10 - 6)
D = 4b
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4b = 7a
4(s + 45) = 7s
4s + 180 = 7s
3s = 180
s = 60
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Answer:
train-a speed: 60 mph
train-b speed: 105 mph
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