A train leaves a station and travels north at a speed of 75 ​km/h. Two hours​ later, a second train leaves on a parallel track and travels north at 125 ​km/h. How far from the station will they​ meet?

Answer 1

It's all about using the distance formula (D = Rate times Time). When the two trains meet, their distances will be the same. So we can say Rate times Time of the first equals Rate times Time of the second -- at that point. We know the rates. We can express the time of the second as T and of the first as T+2 since it left 2 hours earlier. This gives us: 75(T+2) = 125T. Solve for T and T+2. Multiply the second rate by T and the first by T+2. You'll get the same answer in both cases, which is the distance at which they meet.

Answer 2

75X = 125(X-2)

75X = 125X - 250

50X = 250

X = 5 hours

75 times 5 = 375 miles

125 times 3 = 375 miles

they'll meet 375 miles from the station