John M. answered 05/05/16
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Distance = rate x time or D = rt. This can be resolved for time as t = D/r.
If x= speed of train B, then the time it take to travel the distance 260 miles would be 260/x
The speed of train A would be x - 6 since it is 6 mph slower. The time to travel the distance 230 miles would be 230/(x - 6).
If we set them equal to each other since the times are equal:
260/x = 230/(x-6)
Cross multiply to solve:
230x = 260(x-6)
230x = 260x - 1560
-30x = -1560
x= 52 mph (Train B's speed.)
Train A is going 6 mph slower, so it's speed is 46 mph.