# Aptitude Questions: Time And Work Set 12

Hello Aspirants. Welcome to Online Quantitative Aptitude Section with explanation in AffairsCloud.com. Here we are creating question sample in Time and Work, which is common for all the competitive exams . We have included Some questions that are repeatedly asked in bank exams !!

Questions Penned by Yogit

1. If P and Q work together, they will complete a job in 7.5 days. However, if P works alone and completes half the job and then Q takes over and completes the remaining half alone, they will be able to complete the job in 20 days. How long will Q alone take to do the job if P is more efficient than Q?
a) 20 days
b) 30 days
c) 40 days
d) 10 days
e) None of these
Explanation :
1/P + 1/Q = 2/15 from first line. Now, let P take x days and Q takes y days to complete half the work respectively.
x/P = 1/2, x = P/2 similarly y/Q = 1/2, y = Q/2
so, x +y = 20 i.e. P/2 + Q/2 = 20, P +Q = 40
solve both equation, u will get Q = 30 days

2. A and B undertake to complete a piece of work for Rupees 1200. A can do it in 8 days, B can do it in 12 days and with the help of C they complete the work in 4 days. Find the share of C?
a) 100
b) 200
c) 300
d) 400
e) None of these
Explanation :
1/8 + 1/12 + 1/C = 1/4, we get C = 24 days
now efficiency of A, B and C are in the ratio of 1/8 :1/12 : 1/24
3:2:1, so share of C is 1/6 * 1200 = 200

3. Among four persons Anuj, Bhim, Carl and Dinesh. Anuj takes thrice as much time as Bhim to complete a piece of work. Bhim takes thrice as much time as Carl and Carl takes thrice as much time as Dinesh to complete the same work. If all together they take 3 days to complete the work. Find the time taken by Bhim alone to complete the work alone.
a) 20 days
b) 30 days
c) 40 days
d) 50 days
e) None of these
Explanation :
Let Bhim takes x days alone to complete the job, so Anuj will take 3x days, Carl will take x/3 days and Dinesh will take x/9 days to complete the work alone
1/3x + 1/x + 3/x + 9/x = 1/3
Solve for x

4. A and B can do a piece of work in 20 and 25 days respectively. They began to work together but A leaves after some days and B completed the remaining work in 12 days. Number of days after which A left the job-
a) 5.7/9 days
b) 6.7/9 days
c) 7.7/9 days
d) 11.7/9 days
e) None of these
Explanation :
(1/20 + 1/25)*T + 12/25 = 1
We will get T = 52/9 i.e. 5.7/9 days

5. A factory produces nuts and bolts. A machine in it produces only nuts while another produces only bolts. The machine producing only nuts produces 500 nuts per minute and need to be cleared for 10 minutes after production of 2000 nuts. The machine producing only bolts produces 600 bolts per minute and needs to be cleared for 15 minutes after production of 3000 bolts. Find the minimum time required to produce 6000 pairs of bolts and nuts if both machines are operated simultaneously.
a) 32 minutes
b) 20 minutes
c) 25 minutes
d) 40 minutes
e) None of these
Explanation :
2000 nuts are produced in 14 minutes (10 minutes break and 500 nuts per minutes so 4 minutes to produce 2000 nuts ), for next 2000 nuts it will take 14 minutes more, and for more two thousand it will take 4 minutes more, so total time = 32 minutes
similarly, 6000 bolts are produced in 20 + 5 = 25 minutes
so minimum time required is 32 minutes

6. Three professors P, Q, R are evaluating answer script of a subject. P is 40 more efficient than Q, who is 20 more efficient than R. P takes 10 days less than Q to complete the evaluation work. P starts the evaluation work and works for 10 days and then Q takes over. Q evaluates for next 15 days and then stops. In how many days, R can complete the remaining evaluation work?
a) 6.2 days
b) 7.2 days
c) 8.2 days
d) 9.2 days
e) None of these
Explanation :
Let R takes x days to complete the work, then
1/P = (140/100)*1/Q and 1/Q = (120/100)*1/R
So P will take 25x/42 and Q will take 5x/6 days respectively
5x/6 – 25x/42 = 10, we get x = 42
10/25 + 15/35 + t/42 = 1

7. A piece of work has to be completed in 50 days, a number of men are employed but it is found that only half of the work is done in 30 days, then an additional 20 men were joined to complete the work on time. How many men initially put to work?
a) 30
b) 35
c) 40
d) 45
e) None of these
Explanation :
suppose Initially X men get employed. Half work is done in 30 days it means full work will be done by X men in 60 days. Now,
Work done = 1/2 = [20*(x + 20)]/60X
X = 40

8. P can do a piece of work in 20 days. Q is 25 percent more efficient than P. In how many days half the work is completed when both are working simultaneously?
a) 41/9
b) 40/9
c) 39/9
d) 43/9
e) None of these
Explanation :
Q is 25 percent more efficient so he will complete the work in 16 days
(1/20 + 1/16)*t = 1/2

9. A and B together can do a piece of work in 24 days, which B and C together can do it in 32 days. After A has been working at it for 10 days and B for 14 days, C finishes it in 26 days. In how many days C alone will do the work?
a) 32
b) 36
c) 44
d) 48
e) None of these
Explanation :
1/A + 1/B = 1/24 , 1/B + 1/C = 1/32
10/A + 14/B + 26/C = 1
10(1/A + 1/B) + 4(1/B + 1/C) + 22/C = 1
10/24 + 4/32 + 22/C = 1, we get C = 48 days

10. 50 men could complete a work in 200 days. They worked together for 150 days, after that due to bad weather the work is stopped for 25 days. How many more workers should be employed so as to complete the work in time?
a) 25
b) 35
c) 50
d) 60
e) None of these