GMAT Problem Solving (PS) | Re: Two trains, X and Y, started simultaneously from opposite en

I figured out the time they met 't' and then calculated the distance.
D(X) + D(Y) = total Distance = 100
100t/5 + 100t/3 = 100 ; 300t + 500t = 1500 ; t = 15/8
Substitute t in any of the two distance equations. Lets say X:
D = st = 100/5*15/8 = 75/2 = 37.5

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