Numerical Reasoning Speed, Distance, and Time 2 — Questions and Answers
Question 1: Two trains, 200 m and 150 m long, travel toward each other at 40 m/s and 60 m/s respectively. How long does it take for them to completely pass each other?
- 2.5 seconds
- 3 seconds
- 3.5 seconds (Correct answer)
- 4 seconds
Correct answer: 3.5 seconds
Total distance = 350 m; Relative speed = 100 m/s; Time = 350 ÷ 100 = 3.5 seconds.
Question 2: A car travels from city A to city B at 60 mph and returns at 40 mph. What is the average speed for the round trip?
- 48 mph (Correct answer)
- 50 mph
- 52 mph
- 55 mph
Correct answer: 48 mph
Harmonic mean: 2 × 60 × 40 ÷ (60 + 40) = 4800 ÷ 100 = 48 mph.
Question 3: A 300-meter-long train passes a stationary pole in 15 seconds. What is the train's speed in km/h?
- 60 km/h
- 66 km/h
- 72 km/h (Correct answer)
- 80 km/h
Correct answer: 72 km/h
Speed = 300 ÷ 15 = 20 m/s = 20 × 3.6 = 72 km/h.
Question 4: Walking at 6 km/h, a man is 10 minutes late. Walking at 9 km/h, he is 5 minutes early. What is the distance to his destination?
- 3 km
- 4.5 km (Correct answer)
- 6 km
- 7.5 km
Correct answer: 4.5 km
Setting up the equation: d/6 − d/9 = 15/60; solving gives d = 4.5 km.
Question 5: A motorboat travels 24 km upstream and 36 km downstream in equal time. If the stream speed is 4 km/h, what is the boat's speed in still water?
- 16 km/h
- 18 km/h
- 20 km/h (Correct answer)
- 24 km/h
Correct answer: 20 km/h
24/(b−4) = 36/(b+4) gives 24b+96 = 36b−144; solving gives b = 20 km/h.
Question 6: A person jogging at 9 km/h covers a distance in 40 minutes. How long would it take running at 12 km/h to cover the same distance?
- 25 minutes
- 30 minutes (Correct answer)
- 35 minutes
- 45 minutes
Correct answer: 30 minutes
Distance = 9 × (40/60) = 6 km; Time = 6 ÷ 12 = 0.5 hours = 30 minutes.
Question 7: Two cyclists leave the same place at the same time in the same direction at 24 km/h and 16 km/h. After how many hours are they 40 km apart?
- 3 hours
- 4 hours
- 5 hours (Correct answer)
- 6 hours
Correct answer: 5 hours
Relative speed = 24 − 16 = 8 km/h; Time = 40 ÷ 8 = 5 hours.
Numerical Reasoning Speed, Distance, and Time 2
Two trains, 200 m and 150 m long, travel toward each other at 40 m/s and 60 m/s respectively.
How long does it take for them to completely pass each other?