 Aptitude Questions: Time And Work Set 9

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 !!

1. 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

2. P does half as much work as Q in three-fourth of the time. If together they take 36 days to complete the work, then the time taken by Q alone to do the work.
a) 50
b) 55
c) 60
d) 65
e)None of these
Explanation :
Suppose Q take ‘X’ days to complete a job, so to do the same work P will take 2*(3x/4) = 3x/2 days.
1/x + 2/3x = 1/36
X = 60

3. If 20 women and 10 boys can reap a field in 30 days, then in how many days 15 women and 30 boys will reap the field. It is given that work done by 4 women is equal to work done by 3 boys.
a) 210/11 days
b) 200/9 days
c) 200/11 days
d) 210/13 days
e)None of these
Explanation :
20w + 10b = 1/21 (work done by 20 women and 10 boys in one day)
It is given that 4w = 3b
Solve both equation to find the value of w and b,
Then, 15/w + 30/b = 1/d (the days in which 15 women and 30 boys complete the work)

4. If P can do a work in 6 days and Q can do the same work in 8 days. If R who can do the same work in 12 days, joins them, then the work will be completed in how many days?
a) 7/3 days
b) 8/3 days
c) 10/3 days
d) 11/3 days
e)None of these
Explanation :
1/6 + 1/8 + 1/12 = 1/d.
D = 8/3 days

5. A, B and C are three friends that take 20 days to finish a work. The time taken by B is twice the time taken by A and C together and time taken by C to do the work is thrice the time taken by A and B together. How much time will be taken by A alone to do the work.
a) 42 days
b) 44 days
c) 46 days
d) 48 days
e)None of these
Explanation :
1/a + 1/b + 1/c = 1/20 (given)
In first case let time taken by A and C together is p days, then the time taken by B will be 2p. Substitute in the above equation and we get p = 60 (time taken by B to complete the work).
Similarly in the second case, u will get P = 80 (time taken by C to complete the work)
Now, 1/a = 1/20 – 1/60 – 1/80 to get the answer

6. If 4 boys or 5 women can reap a field in 20 days. Then what will be the time taken by 6 boys and 8 women to reap the field.
a) 200/33 days
b) 200/31 days
c) 200/35 days
d) 200/37 days
e)None of these
Explanation :
work done by one boy in one day = 1/(4*20)
Similarly for women = 1/(5*20)
Now the time taken by 6 boys and 8 women to reap the field = 6/80 + 8/100 = 1/d (d = 200/31 will be the answer)

7. 5 men and 10 boys can do a piece of work in 30 days and 8 men and 12 boys can do the work in 20 days then the ratio of daily work done by a man to that of boy.
a) 5:1
b) 6:1
c) 7:3
d) 4:5
e)None of these
Explanation :
5m + 10b = 1/30 and 8m + 12b = 1/20
after solving we get m = 1/200 and b = 1/1200
so required ratio = (1/200) : (1/1200) = 6:1

8. A certain number of men take 45 days to complete a work. If there are 10 men less then they will take 60 days to complete the work. Find the original number of men.
a) 30
b) 40
c) 50
d) 60
e) None of these
Explanation :
Let initially there are X men. Then x*45 = (x-10)*60. So we get x = 40

9. Prakash is twice as fast as sumit and therefore Prakash is able to finish the work in 30 days less than sumit. Find the time in which they can complete the work when both are working together?
a) 25 days
b) 20 days
c) 30 days
d) 35 days
e) None of these
Explanation :
Let sumit take x days then Prakash will take x/2 days to complete the work.
X – X/2 = 30, X = 60
1/60 + 1/30 = 1/d so, we will get d= 20 days

10. 4 women and 5 men working together can do 3 times the work done by 2 women and one man together. Calculate the work of a man to that of woman.
a) 1:2
b) 2:1
c) 1:1
d) 3:2
e) None of these