<PRE><B>Question 541066</B>
Start with the basic distance equation:  d = r*t, where d = distance, r = rate, and t = time.
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Train A
r = x
d = 240 miles
t = 240/x
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Train B
r = x-15
d = 195
t = 195/(x-15)
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We are told the time for the trains is the same, so t=t.
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240/x = 195/(x-15)
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cross multiply
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240*(x-15) = 195*x
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240x -3600 = 195x
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45x = 3600
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x = 80 mph = speed of Train A
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80-15 = 65 mph = speed of Train B
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To check this answer, confirm that t for Train A = t for Train B.
240 miles/80 mph = 3 hr
195 miles/65 mph = 3 hr
Correct.
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Answer: The speed of Train A is 80 mph. The speed of Train B is 65 mph.
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Done.</PRE>