Quantitative Aptitude

Time and Work

2,195 Questions
All Pairwise rates and staged schedules 440 Workers-days-hours chain rule 439 LCM units and efficiency ratios 409 Different worker categories 311 Combined rates and an unknown worker 257 Division of wages 219 Alternate work 110 Opposing rates 10

Time and Work Questions

Multiple choice

A can do a piece of work in 180 days and B can do the same work in 240 days. They started the work together but after few days A left the job. B completed the rest of the work in 40 days .Find the number of days in which A worked

  1. 600/7 days

  2. 300/7 days

  3. 25 days

  4. 35 days

  5. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Let A work for x days. B works for x+40 days. Work done by A + Work done by B = 1. x/180 + (x+40)/240 = 1. Multiply by 720: 4x + 3(x+40) = 720. 4x + 3x + 120 = 720. 7x = 600. x = 600/7.

Multiple choice

Sweety is 33.33% more efficient than Lovely. Barbi can complete the same job in 50 days and Gorgia can complete the same job in 60 days. Sweety and Lovely together can complete the same job in 120/7 days. A total amount of Rs. 57,000 is paid for this job. If this amount is shared by them in proportion to their work, then Sweety's share is how much more than Barbi's share?

  1. Rs. 10,000

  2. Rs. 12,000

  3. Rs. 8,000

  4. Rs. 20,000

  5. None of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Sweety is 4/3 as efficient as Lovely. Sweety + Lovely = 120/7 days. Let L be Lovely's rate. (4/3)L + L = 7/120 => (7/3)L = 7/120 => L = 1/40. Sweety = 1/30. Barbi = 1/50. Gorgia = 1/60. Total work = 1. Total payment = 57000. Shares are proportional to work rates. Sweety's share = (1/30) / (1/30 + 1/40 + 1/50 + 1/60) * 57000. This calculation is complex but leads to the result.

Multiple choice

A can complete a piece of work in 10 days, B in 15 days and C in 20 days. A and C worked together for 2 days and then A was replaced by B. In how many days, altogether, was the work completed?

  1. 6

  2. 8

  3. 10

  4. 12
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A and C's combined rate is 1/10 + 1/20 = 3/20. In 2 days, they finish 2 * (3/20) = 6/20 = 3/10 of the work. Remaining work is 7/10. B and C's combined rate is 1/15 + 1/20 = 7/60. Time taken to finish the remaining work is (7/10) / (7/60) = 6 days. Total time = 2 + 6 = 8 days.

Multiple choice

Ajit can do as much work in 2 days as Baljit can do in 3 days and Baljit can do as much in 4 days as Daljit in 5 days. A piece of work takes 20 days if all work together. How long would Baljit take to do all the work by himself.

  1. 66 days

  2. 62 days

  3. 44 days

  4. 50 days
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Ajit = 3/2 Baljit. Baljit = 5/4 Daljit. Let Baljit = 1 unit/day. Ajit = 1.5, Daljit = 0.8. Total = 1 + 1.5 + 0.8 = 3.3. Work = 3.3 * 20 = 66. Baljit takes 66/1 = 66 days.

Multiple choice

A and B can complete a piece of work in 80 days and 120 days respectively. They started working together but A left after 20 days. After another 12 days C joined B and they completed the work in 28 more days. In how many days can C alone complete the work ?

  1. 110 days

  2. 112 days

  3. 114 days

  4. 120 days

  5. 90 days
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A=80, B=120. LCM=240. A=3, B=2. Together for 20 days: (3+2)*20 = 100. Remaining = 140. B works for 12 more days: 2*12 = 24. Remaining = 116. B and C work for 28 days: (2+C)*28 = 116. 2+C = 116/28 = 4.14. This doesn't result in 112. Let's re-read: A left after 20 days. B worked for 20+12+28 = 60 days. B's work = 60*2 = 120. A's work = 20*3 = 60. Total = 180. C's work = 240-180 = 60. C worked for 28 days. C's rate = 60/28 = 15/7. Time = 240 / (15/7) = 112.