Let the distance travelled by first train till the point they meet be X km. Since the second train travelled 125 Km more than the first one, thusDistance travelled by second train when they meet = X + 125We know that, Time = Distance/SpeedWe know that both trains travelled for the same time till they meet. Hence,⇒ 100X = 75X + 9375⇒ X = 375 Km∴ X + 125 = 500 KmHence the distance between the points P and Q = Distance travelled by train A & B= 375 + 500= 875 Km