Q. 1. A can do a piece of work in 5 days and B can do the same work in 10 days. How many days will both take to complete the work?
(a) 5 days
(b) 3 1/3 days
(c) 3 days
(d) 6 days
(e) None of these
Q. 2. If 12 men can do a piece of work in 24 days, then in how many days can 18 men do the same work?
(a) 36
(b) 20
(c) 18
(d) 16
(e) None of these
Q. 3. A group of workers accepted to do a piece of work in 25 days. If 6 of them did not turn for the work and the remaining workers did the work in 40 days, then the original number of workers was
(a) 22
(b) 20
(c) 18
(d) 16
(e) None of these
Q. 4. If 8 men or 12 women can do a piece of work in 10 days, then the number of days required by 4 men and 4 women to finish the work is
(a) 8
(b) 10
(c) 12
(d) 4
(e) None of these
Q. 5. If 8 men can dig a well in 18 days, then the number of days, 12 men will take to dig the same well will be
(a) 12 days
(b) 10 days
(c) 8 days
(d) 16 days
(e) None of these
Q. 6. 39 men can repair a road in 12 days working 5 hours a day. In how many days will 30 men working 6 hours peer day complete the work?
(a) 10
(b) 13
(c) 14
(d) 15
(e) None of these
Q. 7. A certain number of men can do a work in 40days. If there were 8 men more, it could be finished in 10 days less. How many men were there initially?
(a) 30
(b) 24
(c) 16
(d) 20
(e) None of these
Q. 8. If 4 men or 6 boys can finish a work in 20 days. How long will 6 men and 11 boys take to finish the same work?
(a) 10 days
(b) 6 days
(c) 4 days
(d) 3 days
(e) None of these
Q. 9. A works twice as fast as B. if B can complete a work in 12 days independently. The number of days in which A and B can together finish the work?
(a) 18 days
(b) 8 days
(c) 6 days
(d) 4 days
(e) None of these
Q. 10. A and B can do a piece of work in 4 days. If A can do it alone in 12 days, B will finish the work in
(a) 4 days
(b) 6 days
(c) 8 days
(d) 10 days
(e) None of these
Ans: 1. (b) 3 1/3 days
Explanation:
If A can complete a work in x days and B can complete the same work in y days, then, both of them together can complete the work in x y/ x+ y days. That is, the required No. of days = 5 × 10/15 = 3 1/3 days.
Ans: 2. (d) 16
Explanation:
1 work done = 12 × 24
Then, 12 × 24 = 18 × ? days
? days = 12 × 24/18 = 16.
Ans: 3. (d) 16
Explanation:
Let the original number of workers be ‘x’
Then, x × 25 = (x – 6) × 40
25x = 40x -240
240 = 40x -25x = 15x
x = 240/15 = 16.
Ans: 4. (c) 12
Explanation:
8 men = 12 women
1 woman = 8/12 men = 2/3 men
4 women = 2/3 × 4 men = 8/3 men
4 men + 4 women = 4 + 8/3 men = 20/3 men
1 work done = 8 × 10
8 × 10 = 20/3 × ?days
?days = 8 × 10 × 3/20 = 12 days.
Ans: 5. (a) 12 days
Explanation:
Work done = 8 × 18
Then, 8 × 18 = 12 × ? days
? days = 8 × 18/12 = 12 days.
Ans: 6. (b) 13
Explanation:
1 work done = 39 × 12 × 5
39 × 12 × 5 = 30 × 6 × ?days
? days = 39 × 12 × 5/ 30 × 6 = 13 days.
Ans: 7. (b) 24
Explanation:
Let ‘x’ be the initial number of men
Then, 1 work done = x × 40
Then, x × 40 = (x + 8 ) (40 – 10)
40x = 30x + 240
10x = 240
Therefore, x = 240/10 = 24 men.
Ans: 8. (b) 6 days
Explanation:
4 men = 6 boys
Then, 1 boy = 4/6 men = 2/3 men
11 boys = 2/3 × 11 men = 22/3 men
Then, 6 men + 11 boys = 6 + 22/3 men = 40/3 men
1 work done = 4 men × 20 days
That is, 4 × 20 = 40/3 × ? days
? days = 4 × 20 × 3/40 = 6 days.
Ans: 9. (d) 4 days
Explanation:
If B takes 12 days to finish the work, then A takes 6 days to finish the same work.
If A can complete a work in x days and B can complete the same work in y days, then, both of them together can complete the work in x y/ x+ y days.
Therefore, the Number of days taken by A and B together to finish the same work = 6 × 12/18 = 4 days.
Ans: 10. (b) 6 days
Explanation:
If A and B together can do a piece of work in x days and A alone can do the same work in y days, then B alone can do the same work in x y/ y – x days.
Therefore, the number of days B will take to finish the work = 4 × 12/ 12 – 4 = 48/8 = 6 days.
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