Quantitative Aptitude | Questions
Time and Work questions with solutions
Time and Work is a Quantitative Aptitude topic for competitive exams. It is tested in RRB Ministerial and Isolated Categories, RPF SI, RRB Section Controller, RPF Constable and other exams. This page has 29 solved time and work questions written to the official pattern, with a worked solution under each.
- Question 1Easy
8 workers finish a task in 10 days. How many days will 5 workers take at the same rate?
- A.10
- B.18
- C.22
- D.16Correct
- E.14
Show solution
The work is 10×8 = 80 worker-days, so 5 workers take 80/5 = 16 days.
- Question 2Easy
12 workers finish a task in 18 days. How many days will 6 workers take at the same rate?
- A.38
- B.36Correct
- C.50
- D.22
- E.34
Show solution
The work is 18×12 = 216 worker-days, so 6 workers take 216/6 = 36 days.
- Question 3Easy
12 men can complete a work in 15 days. How many days will 20 men take to do the same work?
- A.9Correct
- B.12
- C.8
- D.10
Show solution
The work is 12 × 15 = 180 man-days. With 20 men it takes 180 ÷ 20 = 9 days.
- Question 4Easy
8 workers finish a task in 24 days. How many days will 4 workers take at the same rate?
- A.48Correct
- B.32
- C.64
- D.50
- E.46
Show solution
The work is 24×8 = 192 worker-days, so 4 workers take 192/4 = 48 days.
- Question 5Moderate
12 workers finish a task in 10 days. How many days will 8 workers take at the same rate?
- A.10
- B.15Correct
- C.20
- D.21
- E.9
Show solution
The work is 10×12 = 120 worker-days, so 8 workers take 120/8 = 15 days.
- Question 6Moderate
9 workers finish a task in 20 days. How many days will 10 workers take at the same rate?
- A.23
- B.18Correct
- C.26
- D.13
- E.10
Show solution
The work is 20×9 = 180 worker-days, so 10 workers take 180/10 = 18 days.
- Question 7Moderate
4 workers complete a job in 12 days. How many days will 6 workers take at the same rate?
- A.8Correct
- B.18
- C.6
- D.9
Show solution
Total work = 4 × 12 = 48 worker-days. With 6 workers, time = 48/6 = 8 days.
- Question 8Moderate
A can do a piece of work in 12 days and B in 6 days. Working together, in how many days will they finish it?
- A.4Correct
- B.5
- C.3
- D.6
Show solution
In one day A does 1/12 and B does 1/6 = 2/12, together 3/12 = 1/4 of the work, so they finish in 4 days.
- Question 9Moderate
A can finish a task in 10 days and B in 15 days. Working together, how many days will they take?
- A.6Correct
- B.5
- C.8
- D.12
Show solution
A's rate = 1/10 per day, B's rate = 1/15 per day. Combined rate = 1/10 + 1/15 = 5/30 = 1/6. So together they finish in 6 days.
- Question 10Moderate
A can complete a piece of work in 15 days and B in 10 days. Working together, in how many days will they finish it?
- A.5
- B.6Correct
- C.7
- D.8
- E.9
Show solution
In one day A does 1/15 and B does 1/10 of the work. Together that is 1/15 + 1/10 = 2/30 + 3/30 = 5/30 = 1/6 per day, so the whole work takes 6 days. The LCM method also works: let the work be 30 units, A does 2 a day and B does 3, giving 5 a day and 30 / 5 = 6 days.
- Question 11Moderate
A can complete a piece of work in 12 days and B can complete the same work in 18 days. Working together, in how many days will they finish it?
- A.6 3/5 days
- B.7 1/5 daysCorrect
- C.7 2/5 days
- D.7 1/2 days
- E.8 days
Show solution
In one day A does 1/12 of the work and B does 1/18. Together that is 1/12 + 1/18. Using an LCM of 36: 3/36 + 2/36 = 5/36 per day. The whole work therefore takes 36/5 = 7.2 days, which is 7 1/5 days. A faster route is the LCM method: let the work be 36 units, so A does 3 units a day and B does 2, giving 5 units a day and 36/5 days.
- Question 12Moderate
A can finish a task in 12 days and B in 18 days. Working together, in how many days will they finish it?
- A.6.0
- B.7.2Correct
- C.7.5
- D.8.4
- E.9.0
Show solution
In one day A does 1/12 and B does 1/18. Together that is 3/36 + 2/36 = 5/36 of the task per day, so the whole task takes 36 / 5 = 7.2 days. Add the rates, then invert; never add the days.
These are 12 of 29 time and work questions in the bank. Attempt the rest with instant feedback in the practice drills, or under a clock in the mock tests.
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Frequently asked questions
How many Time and Work questions are here?
This page shows 12 worked time and work questions from a bank of 29, spanning 4 easy, 17 moderate and 8 hard. The full set is available to attempt in the timed-free practice drills and the mock tests.
Which exams ask Time and Work questions?
Time and Work is part of the Quantitative Aptitude syllabus for RRB Ministerial and Isolated Categories, RPF SI, RRB Section Controller, RPF Constable, RRB JE, RRB Technician, RRB ALP, RRB Group D, NABARD Office Attendant, RBI Office Attendant, RRB NTPC. Weightage varies by exam and stage — check each exam's page for its pattern.
Are these Time and Work questions free, and are the answers reliable?
Yes. Every question is free, written in-house to the exam pattern rather than copied from a real paper, and the numeric answer keys are recomputed independently at build time — a wrong key fails the build rather than reaching you.