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put this solution on YOUR website!train B xmph
train A = x-10 mph
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train A 210 miles
train B 260 miles
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Time taken by both the trains is same
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260/x =210/x-10
260(x-10)=210x
260x-2600=210x
50x=2600
x=52 mph speed of train B
train A speed = 42mph