Time, Speed, Distance & Work

What you'll learn

One idea -- Rate x Time = Total -- powers trains, average speed, relative speed, and pipes & cisterns. Learn the 5/18 shortcut, the average-speed trap, and the add-the-rates method to lock in easy RRB NTPC Maths marks.

This chapter has

Time, Speed, Distance & Work — solved practice questions

8 Railways Mathematics questions with step-by-step solutions. Attempt each, then reveal the answer.

1. Q1easy

   A car travels at 60 km/h for 3 hours. What distance does it cover?

   • A120 km
   • B180 km
   • C150 km
   • D200 km
   Show answer & solution

   Correct answer: (B) 180 km

   Distance = speed × time = 60 × 3 = 180 km.

2. Q2easy

   Convert 72 km/h into metres per second.

   • A18 m/s
   • B25 m/s
   • C20 m/s
   • D36 m/s
   Show answer & solution

   Correct answer: (C) 20 m/s

   Multiply by 5/18: 72 × 5/18 = 20 m/s.

3. Q3medium

   A train 150 m long is running at 90 km/h. How long does it take to cross a pole?

   • A6 seconds
   • B5 seconds
   • C8 seconds
   • D10 seconds
   Show answer & solution

   Correct answer: (A) 6 seconds

   90 km/h = 25 m/s. Time = 150 ÷ 25 = 6 seconds.

4. Q4medium

   A can do a piece of work in 10 days and B in 15 days. How long will they take working together?

   • A12 days
   • B5 days
   • C25 days
   • D6 days
   Show answer & solution

   Correct answer: (D) 6 days

   Combined rate = 1/10 + 1/15 = 1/6 per day, so together they take 6 days.

5. Q5medium

   If 5 men can finish a job in 8 days, how many days will 8 men take for the same job?

   • A4 days
   • B5 days
   • C6 days
   • D10 days
   Show answer & solution

   Correct answer: (B) 5 days

   Total work = 5 × 8 = 40 man-days. With 8 men, days = 40 ÷ 8 = 5.

6. Q6easy

   A distance of 240 km is covered in 4 hours. What is the average speed?

   • A50 km/h
   • B55 km/h
   • C60 km/h
   • D65 km/h
   Show answer & solution

   Correct answer: (C) 60 km/h

   Speed = distance ÷ time = 240 ÷ 4 = 60 km/h.

7. Q7hard

   A pipe fills a tank in 6 hours and another in 8 hours. Working together, how long do they take to fill it?

   • A3 3/7 hours
   • B4 hours
   • C2 hours
   • D14 hours
   Show answer & solution

   Correct answer: (A) 3 3/7 hours

   Combined rate = 1/6 + 1/8 = 7/24 per hour, so time = 24/7 = 3 hours 26 minutes (3 3/7 hours).

8. Q8easy

   A boat's speed in still water is 10 km/h and the stream flows at 2 km/h. What is its downstream speed?

   • A8 km/h
   • B10 km/h
   • C20 km/h
   • D12 km/h
   Show answer & solution

   Correct answer: (D) 12 km/h

   Downstream speed = boat speed + stream speed = 10 + 2 = 12 km/h.

Want the full set? Practise all 15 Time, Speed, Distance & Work questions →