Question

Two trains, X and Y, travel from A to B at average speeds of 80 km/hr and 90 km/hr respectively. If X takes an hour more than Y for the journey, then the distance between A and B is _____.

• A. 360 km
• B. 720 km
• C. 540 km
• D. 630 km

Answer 1

Answer:

B. 720 km

Let distance be x km x/80 – x/90 = 1 ⇒ (9x – 8x)/720 = 1 ⇒ x = 720 km