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

Peeyush has done 1/3rd of a job in 30 days, Sanjiv completes the rest of the job in 60 days. In how many days can they together do the job?

  1. 15 days

  2. 45 days

  3. 30 days

  4. 10 days
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Peeyush does 1/3 of the job in 30 days, so he does the whole job in 90 days. Sanjiv does the remaining 2/3 of the job in 60 days, so he does the whole job in 90 days. Together, their rate is 1/90 + 1/90 = 2/90 = 1/45, meaning they take 45 days.

Multiple choice

Ashish can complete a piece of work in 12 days, Balraj in 15 days and Chintoo in 20 days. All of them together started the work, but Chintoo left when he realised that the remaining work will be completed without him in the next 2 days, and Balraj left when he realised that the remaining work will be completed without him in the next one day. Find the total number of days taken to complete the work.

  1. 5 17 18

  2. 5 13 18

  3. 5 3 5

  4. 4 17 18
Reveal answer Fill a bubble to check yourself
A Correct answer
Multiple choice

Atul can complete a piece of work in 'c' days by working 'e' hours per day. Balwinder can complete the same work in 'f' days by working 'g' hours per day. If each of them reduces his working hours by 4 hours, each of them would take 5 days more to finish the work. How long would it take to complete the work, if Atul and Balwinder started working together such that Atul worked for 'e' hours per day and Balwinder worked for 'g' hours per day? It is to be noted that 'c', 'e', 'f' and 'g' are distinct natural numbers and 'e', 'g' < 16.

  1. 10/3 days

  2. 4 days

  3. 5 days

  4. Cannot be determined

  5. 10 days
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Total work is c*e = f*g. The condition (e-4)(c+5) = ce and (g-4)(f+5) = fg leads to equations that allow solving for the work rate. Given the constraints, the combined rate calculation results in 10/3 days.

Multiple choice

Praful has done 1/2 of a job in 30 days, Sarabjit completes the rest of the job in 10 days. In how many days can they together do the job?

  1. 30 days

  2. 45 days

  3. 15 days

  4. 60 days
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Praful does 1/2 of the job in 30 days, so he takes 60 days to complete the whole job. Sarabjit completes the remaining 1/2 in 10 days, so he takes 20 days to complete the whole job. Their combined daily rate is 1/60 + 1/20 = 1/60 + 3/60 = 4/60 = 1/15, meaning they take 15 days together.

Multiple choice

Akhilesh is two times as good a workman as Bansi and is able to finish a job in 39 days less than Bansi. Working together, they can do it in

  1. 13 days

  2. 24 days

  3. 26 days

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

Let Bansi take x days. Akhilesh takes x - 39 days. Efficiency ratio A:B = 2:1, so time ratio A:B = 1:2. Thus, x = 2(x - 39) => x = 2x - 78 => x = 78. Akhilesh takes 39 days, Bansi takes 78 days. Together: (39 * 78) / (39 + 78) = 3042 / 117 = 26 days.