While Preparing forEntranceAptitude Exams, questions on Time and work are asked frequently. Here the concepts and formulas should be understood well.

We have provided the selective and important Time and work questions and answers for various Aptitude tests and competitive exams. Try to solve maximum questions to increase your performance in exams.

Time and Work Questions With Answers

Q1) P is able to do a piece of work in 15 days and Q can do the same work in 20 days. If they can work together for 4 days, what is the fraction of work left?

A) 7/15

B) 11/15

C) 2/11

D) 8/15

Solution :

Q2) P, Q and R can do a work in 20, 30 and 60 days respectively. How many days does it need to complete the work if P does the work and he is assisted by Q and R on every third day?

A) 15 days

B) 9 days

C) 10 days

D) 14 days

Solution :

Q3) To complete a piece of work A and B take 8 days, B and C 12 days. A, B and C take 6 days. A and C will take :

A) 7 Days

B) 7.5 Days

C) 8 Days

D) 8.5 Days

Solution :

Q4) A can do a particular work in 6 days. B can do the same work in 8 days. A and B signed to do it for Rs. 3200. They completed the work in 3 days with the help of C. How much is to be paid to C?

A) Rs. 600

B) Rs. 420

C) Rs. 400

D) Rs. 380

Solution :

Q5) A is twice as good a workman as B and is therefore able to finish a piece of work in 30 days less than B. In how many days they can complete the whole work; working together?

A) 10 Days

B) 20 Days

C) 30 Days

D) 40 Days

Solution :

Ratio of times taken by A and B = 1 : 2.
The time difference is (2 - 1) 1 day while B take 2 days and A takes 1
day.
If difference of time is 1 day, B takes 2 days.
If difference of time is 30 days, B takes 2 x 30 = 60 days.
So, A takes 30 days to do the work.
A's 1 day's work = 1/30
B's 1 day's work = 1/60
(A + B)'s 1 day's work = 1/30 + 1/60 = 1/20
A and B together can do the work in 20 days.

Q6) Susan can type 10 pages in 5 minutes. Mary can type 5 pages in 10 minutes. Working together, how many pages can they type in 30 minutes?

A) 15

B) 20

C) 25

D) 75

Solution :

(30/5=6; 6*10=60; Susan will type 60 pages in 30 min. 30/10=3;
5*3=15; Mary will type 15 pages in 30 min. 60+15=75)

Q7) A and B together can complete a task in 20 days. B and C together can complete the same task in 30 days. A and C together can complete the same task in 30 days. What is the respective ratio of the number of days taken by A when completing the same task alone to the number of days taken by C when completing the same task alone?

A) 1:3

B) 2:4

C) 3:1

D) 4:5

Solution :

Efficiency of A and B = 1/20 per day = 5% per day ________________1
Efficiency of B and C = 1/30 per day = 3.33% per day______________2
Efficiency of C and A = 1/30 per day = 3.33% per day______________3
Taking equation 2 and 3 together
B + C = 3.33% and C + A = 3.33%
C and 3.33% will be removed. Hence A = B
Efficiency of A = B = 5%/2 = 2.5% = 1/40
Efficiency of C = 3.33% - 2.5% = 0.833% = 1/120
A can do the job in 40 days and C can do the job in 120 days he they
work alone.
Ratio of number of days in which A and C can complete the job 1:3.

Q8) Worker A takes 8 hours to do a job. Worker B takes 10 hours to do a job. How long should it take both A and B, working together to do the same job?

A) 4/9

B) 22/9

C) 31/9

D) 40/9

Solution :

In this type of questions, first we need to calculate 1 hours work, then
their collective work as A's 1-hour work is 1/8
B's 1-hour work is 1/10
(A+B)'s 1 hour work = 1/8 + 1/10= 9/40
So both will finish the work in 40/9 hours

Q9) A takes twice as much time as B or thrice as much time as C to finish a piece of work. Working together, they can finish the work in 2 days. B can do the work alone in

A) 4 days

B) 8 days

C) 6 days

D) 12 days

Solution :

Suppose A, B and C take x, x/2 and x/3 days respectively to finish the
work.
Then, 1/x + 2/x + 3/x = 1/2
6/x = 1/2
x = 12.
So, B takes (12/2) = 6 days to finish the work.

Q10) A can do a piece of work in 5 days and B do the same work in 6 days. If A and B work together they will complete the work?

A) 9(3/5) days

B) 9(3/5) days

C) 9(2/5) days

D) 30/11 days

Solution :

A`s one day work is =1/5. 1/5*30=6
5+6=11/30
B`s one day work is =1/6. 1/6*30=5
One day work of A and B is =11/30
So they will complete the work in 30/11 days.