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

X is thrice as good as Y to do a job and is able to complete a work in 30 days less than Y. Working together, they can do the job on the

  1. 25th day

  2. 12th day

  3. 14th day

  4. 11th day
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Let Y take x days; then X takes x/3 days. Given x - x/3 = 30, we find x = 45 days for Y and 15 days for X. Their combined rate is 1/45 + 1/15 = 4/45, meaning they finish in 45/4 = 11.25 days. They complete the work during the 12th day.

Multiple choice

Directions: The following question is accompanied by statements A, B and C. You have to determine which of the statements is/are sufficient/necessary to answer the question. How much time will Amit and Beth take together to complete a piece of work? A. Amit is 50% more efficient than Beth. B. Charlie will complete that work in 10 days. C. Beth completes that piece of work in 24 days.

  1. All together are necessary.

  2. Only A is sufficient.

  3. A and C together are sufficient.

  4. C and B together are sufficient.

  5. Either A or B is sufficient.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A gives the ratio of efficiencies (Amit = 1.5 * Beth). C gives Beth's time. With both, we can find Amit's time and their combined rate. B is irrelevant.

Multiple choice

Vibhu alone can do a piece of work in 40 days, whereas Kashish alone can do the same work in 56 days. They started the work together. Then, due to some reason, Vibhu left 13 days before the work was completed. In approximately how many days in total was the work completed?

  1. 27 days

  2. 28 days

  3. 31 days

  4. 45 days

  5. 46 days
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Let total days be x. Vibhu works for (x-13) days, Kashish works for x days. (x-13)/40 + x/56 = 1. Multiply by 280: 7(x-13) + 5x = 280. 7x - 91 + 5x = 280. 12x = 371. x = 30.91, which is approximately 31 days.

Multiple choice

Direction : Study the following questions carefully and choose the right answer. Amar, Akbar and Anthony take up a task to finish for Rs. 876. Amar completes his assignment in 4 days, Akbar does it in 8 days and Anthony takes 12 days to finish it. They complete the work with the help of there mother Nirupama in 2 days. What does Nirupama get?

  1. Rs. 307

  2. Rs. 73

  3. Rs. 75

  4. Rs. 267

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

Their combined work rate is 1/4 + 1/8 + 1/12 = 11/24 of the task per day. In two days they complete 11/12 of the task, leaving Nirupama to complete 1/12. Her share is therefore Rs. 876/12 = Rs. 73.

Multiple choice

A can do a piece of work in 20 days and B can do the 1/7th of the same work in 5 days. In how many days together they can complete the 11/14th of the total work?

  1. 140/11 days

  2. 15 Days

  3. 20 Days

  4. 10 Days

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

A can complete the work in 20 days, and B can complete the entire work in 35 days. Their combined rate is 1/20 + 1/35 = 11/140 of the work per day, meaning they will take 10 days to complete 11/14 of the total work.

Multiple choice

Two persons Aman and Bhanu can dig a pit in 20 days and 25 days respectively and a third person Cheenu can fill that pit in 50 days. All of the three persons start their work and after sometime Cheenu leaves the work. If total time taken to dig the pit from the beginning is 13 days, find after how many days Cheenu left his work?

  1. 8.5 days

  2. 7.5 days

  3. 9.5 days

  4. 8 days

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

Aman rate = 1/20, Bhanu = 1/25, Cheenu = -1/50. Let t be the time Cheenu worked. (1/20 + 1/25 - 1/50)t + (1/20 + 1/25)(13-t) = 1. (5/100 + 4/100 - 2/100)t + (9/100)(13-t) = 1. 0.07t + 1.17 - 0.09t = 1. 0.17 = 0.02t. t = 8.5 days.

Multiple choice
  1. In how many days 10 men can finish the work?I. 10 women finish the work in 6 days.II. 10 men and 10 women finish the work in 24/7 days.III. If 10 women work 3 days and after that 10 men are deployed to work for women, the rest work is finished in 4 days.

  1. I and II are sufficient

  2. I and III are sufficient

  3. Any two of three are sufficient.

  4. II and III are sufficient.

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

Let M and W be the work rates of one man and one woman. I: 10W = 1/6. II: 10M + 10W = 7/24. III: 30W + 40M = 1. Any two equations are sufficient to find M and W, and thus the time for 10 men.