WORK-TIME AND UNITARY METHOD (CDS)

Total Questions: 53

1. A stock of food grains is enough for 240 men for 48 days. How long will the same stock last for 160 men? [2019 (II) Evening Shift ]

Correct Answer: (a) 72 days
Solution:Let total stock of food grains be 1 unit.

2. Two taps X and Y are fixed to a water tank. If only X is opened, it drains out the full tank of water in 20 min. If both X and Y are opened, then they drain out the full tank of water in 15 min. If only Y is opened, how long does it take to drain out the full tank of water? [2019 (II) Evening Shift ]

Correct Answer: (c) 60 min
Solution:X drains out full tank in 20 min.

3. If the ratio of the work done by (x + 2) workers in (x − 3) days to the work done by (x + 4) workers in (x − 2) days is 3 : 4, then what is the value of x ? [2019 (II) Evening Shift ]

Correct Answer: (b) 10
Solution:Number of workers (x + 2) worked for (x - 3) days and (x + 4) workers worked for (x - 2) days.

4. A field can be reaped by 12 men or 18 women in 14 days. In how many days can 8 men and 16 women reap it? [2019 (II) Evening Shift ]

Correct Answer: (c) 9 days
Solution:A field can be reaped by 12 men or 18 women in 14 days.

5. Tushar takes 6 h to complete a piece of work, while Amar completes the same work in 10 h. If both of them work together, then what is the time required to complete the work? [2019 (II) Evening Shift ]

Correct Answer: (d) 3 h 45 min
Solution:Tushar takes 6 h to complete a piece of work. While Amar complete the same work in 10 h.

6. Two workers ‘A’ and ‘B’ working together completed a job in 5 days. Had ‘A’ worked twice as efficiently as he actually did and ‘B’ worked one-third as efficiently as he actually did, the work would have completed in 3 days. In how many days could ‘A’ alone complete the job? [2018 (II) Evening Shift ]

Correct Answer: (d) 6¼ days
Solution:Let the efficiency of A and B be ‘a’ and ‘b’ respectively.


7. ‘A’ is thrice as good a workman as ‘B’ and takes 10 days less to do a piece of work than ‘B’ takes. The number of days taken by ‘B’ alone to finish the work is [2018 (II) Evening Shift ]

Correct Answer: (b) 15
Solution:Let A can finish the work = x days

8. Twelve (12) men work 8 h per day and require 10 days to build a wall. If 8 men are available, how many hours per day must they work to finish the work in 8 days? [2018 (II) Evening Shift ]

Correct Answer: (c) 15 h
Solution:12 men can do a work in 10 days if they work 8 h per day.

9. X and Y together can finish a job in 6 days. X can alone do the same job in 12 days. How long will Y alone take to do the same job? [2018 (II) Evening Shift ]

Correct Answer: (b) 12 days
Solution:X can do the job in 12 days

10. Twelve (12) persons can paint 10 identical rooms in 16 days. In how many days can 8 persons paint 20 such rooms? [2018 (II) Evening Shift ]

Correct Answer: (d) 48
Solution:12 persons can paint 10 identical rooms in 16 days.