Multiple choice

Passage

Directions: Read the passage below and answer the questions that follow. The Ludhiana-New Delhi superfast express departs Ludhiana Railway station for New Delhi railway station at 7:00 a.m. in the morning travelling at an average speed of 60 km/hr. The New Delhi-Ludhiana express departs New Delhi railway station for Ludhiana exactly an hour later travelling at an average speed of 100 km/hr. The distance between the two railway stations is 300 km.

After travelling for 1 hr, the locomotive of the New Delhi - Ludhiana express develops a snag due to which the train is halted enroute. The locomotive is then repaired and the train starts running again after having halted for 45 minutes. At what speed must the train now run to make up for the lost time?

  1. 133 km/hr

  2. 152 km/hr

  3. 160 km/hr

  4. 171 km/hr

  5. Cannot be determined
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The train travels 100 km in 1 hour before the snag. It halts for 45 minutes (0.75 hours). To cover the remaining 200 km in the original remaining time (300 km total / 100 km/hr = 3 hours total, minus 1 hour already traveled = 2 hours left), it must cover 200 km in 1.25 hours (2 hours - 0.75 hours). Speed = 200 / 1.25 = 160 km/hr.

AI explanation

To reach New Delhi exactly on time, the New Delhi - Ludhiana express must cover the 300 km distance in its normal duration of 300/100 = 3 hours, meaning it must arrive at 11:00 a.m. By the time the train is repaired, it has travelled for 1 hour and halted for 45 minutes, so it resumes at 9:45 a.m. The train has already covered 100 km, leaving 200 km, and it has exactly 1 hour and 15 minutes or 1.25 hours until 11:00 a.m. Using the formula speed equals distance divided by time, the required speed is 200/1.25, which gives 160 km/hr.

Keep practicing — related questions