Quantitative Aptitude

Time, Work, and Projects

190 Questions

Time and work questions test the ability to calculate the time required to complete tasks involving individual or combined worker efficiency. These problems frequently appear in competitive exams to assess logical calculation skills. Topics include pipes, cisterns, group efficiency, and hourly work rates.

Combined work efficiencyMen and days calculationsWorker efficiency ratiosWorking hours per dayLeaving and joining workers

Time, Work, and Projects Questions

Multiple choice technology

Lead time required for Scheduling a new job through CMR

  1. 1 Day

  2. 1 week

  3. 8 Days

  4. 3 Days
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

CMR scheduling requires advance notice to ensure resource allocation and job preparation. 8 days allows sufficient time for processing, validation, and queue placement. Shorter timeframes (1-3 days) are typically insufficient for proper scheduling procedures.

Multiple choice

5 skilled workers can build a wall in 20days: 8 semi-skilled workers can build a wall in 25 days; 10 unskilled workers can build a wall in 30days. If a team has 2 skilled, 6 semi-skilled and 5 unskilled workers, how long will it take to build the wall?

  1. 20

  2. 18

  3. 16

  4. 15
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

For skilled: men -> days -> amount of wall

5 -> 20  -> 1
1 -> 100 -> 1
1 -> 1   -> 1/100
For semi-skilled: men -> days -> amount of wall

8 -> 25  -> 1

1 -> 200 -> 1
1 -> 1   -> 1/200
For unskilled: men -> days -> amount of wall

10 -> 30  -> 1

1  -> 300 -> 1
1  -> 1   -> 1/300
Amount of work 2 skilled in 1 day = 2/100 Amount of work 6 semi-skilled in 1 day = 6/200 Amount of work 5 unskilled in 1 day = 5/300

Total work in 1 day 

= 2/100+6/200+5/300
= 12/600+18/600+10/600
= 1/15

So complete work will take 15 days

Multiple choice

A transporter receives the same number of orders each day. Currently, he has some pending orders (backlog) to be shipped. If he uses 7 trucks, then at the end of the 4th day he can clear all the orders. Alternatively, if he uses only 3 trucks, then all the orders are cleared at the end of the 10th day. What is the minimum number of trucks required so that there will be no pending order at the end of the 5th day?

  1. 4

  2. 5

  3. 6

  4. 7
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Let each truck carry 100 units. 2800 = 4n + e n = normal 3000 = 10n + e e = excess/pending             $\therefore$$ n =\dfrac{100}{3}, e =\dfrac{8000}{3} $             5days $\Rightarrow$$500x = \dfrac{5.100}{3} + \dfrac{8000}{3}$             $\Rightarrow$$500x = \dfrac{8500}{3}17 \Rightarrow x > 5$ Minimum possible = 6

Multiple choice

We are given 9 tasks T1,T2,........T9. The execution of each task requires one unit of time. We can execute one task at a time. Ti has a profit Pi and a deadline di profit Pi is earned if the task is completed before the end of the d1th unit of time.

Are all tasks completed in the schedule that gives maximum profit?

  1. All tasks are completed

  2. T1 and T6 are left out

  3. T1 and T8 are left out

  4. T4 and T6 are left out
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Multiple choice

X completes 40% of his work in 12 days. Then takes the help of Y and Z. Y is 50% efficient as X, Z is 50% efficient as Y. In how many more days will they complete the work?

  1. 18 days

  2. 72/7 days

  3. 6 days

  4. 144 days

  5. 72/3 days
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

When X is doing 40 % of work, it takes 12 days.
When X is doing 60% of work, it takes 18 days. When X + Y + Z or X + 1/2X + 1/4X is doing 60% of work it takes 18/(1 + 1/2 + 1/4) = 72/7 days.

Multiple choice

There are twenty people working in an office. The first group of five works between 8:00 a.m. and 2:00 p.m. The second group of ten works between 10:00 a.m. and 4:00 p.m. The third group of five works between 12 noon and 6:00 p.m. There are three computers in the office which all the employees frequently use. During which of the following hours are the computers likely to be used the most?

  1. 10:00 a.m. – 12 noon

  2. 12 noon – 2:00 p.m.

  3. 1:00 p.m. – 3:00 p.m.

  4. 2:00 p.m. – 4:00 p.m.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Clearly, the computers would be used the most when all the three groups are working simultaneously and this happens during the period of 12 noon to 2:00 p.m.

Multiple choice

Suman takes thrice as much time as Rahul and four times as much as Varun to finish a task. They together complete the task in one day. Find the time taken by each of them to complete the task.

  1. 6 days

  2. 14 days

  3. 5 days

  4. 10 days

  5. 8 days
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

It is correct answer.

Let alone time of Suman be x .

Then alone time of Rahul = x/3 and that of Varun be x/4.

Suman's one day work + Rahul's one day work + Varun's one day work = Combined one day work                     

   (1/x) + (1/(x/3)) + (1/(x/4)) = 1                                                  x = 8

Multiple choice

A and B can do a piece of work in 6 days. B and C can do it in 7½ days. C and A can do it in 10 days. In how many days will B alone finish it?

  1. 30 days

  2. 10 days

  3. 15 days

  4. 1/10 days
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

( A + B ) 's  1 day work  = 1 / 6( B + C ) 's 1 day work = 2 / 15       ( 7 1/2 = 15 /2 ) ( C + A )'s 1 day work = 1/ 10By adding

( A+ B ) + ( B + C ) + ( C + A ) 's 1 day work = 1/ 6 + 2/15 + 1/10  (A + B + B + C + C + A) 's 1 day work = 1/ 6 + 2/15 + 1/10  ( 2A + 2B + 2C ) 's 1 day work = 1/6 + 2/15 + 1/10 2 ( A + B + C ) 's 1 day work = (5 + 4 + 3) /30 = 12/30 = 6 /15 (A + B + C )'s 1 day work = 6/15 x 2 = 6/30

( A + B + C ) 's 1 day work - ( C + A ) 's 1 day work =                                  6/30 - 1/10                                 = 6 - 3 /30                                = 3/30                                  = 1 /10 B1 day work is 1/10 B can complete whole work in  1 / 1/10 = 10 days

Multiple choice

The work done by A in one day is half of the work done by B in one day. The work done by B is half of the work done by C in one day. If C alone can complete the work in 7 days, in how many days will A, B and C together complete the work?

  1. 28 days

  2. 14 days

  3. 4 days

  4. 21 days

  5. 8 days
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Work done by C in one day = 1/7 Work done by B in one day = 1/2(C) = 1/7 x 1/2 = 1/14 Work done by A in one day = 1/2(B) = 1/2 x 1/14 = 1/28 Work done by A, B and C together in one day = (4 + 2 + 1)/28 = 1/4 Work is done by A, B and C together in 4 days.

Multiple choice

A can do a piece of work in 10 days and B can do the same work in 14 days. How long will they take if both of them work together?

  1. 35/6 days

  2. 6/35 days

  3. 6 days

  4. 60/11 days

  5. 12 days
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A's 1 day's work = 1/10th part of the whole work and  B's 1 day's work = 1/14th part of the whole work. Therefore, (A + B)'s one day's work = 1/10 + 1/14 = 6/35th part of the whole work. So, both will complete the work in 35/6 days. It is the correct answer.