Aptitude Questions on Time-Work

  1. A can do a work in 15 days and B in 20 days. If they work on it together for 4 days, then the fraction of the work that is left is:
    A. 1/4
    B. 1/10
    C. 7/15
    D. 8/15
  2. D. 8/15
    A's 1 day's work = 1/15
    B's 1 day's work = 1/20
    (A + B)'s 1 day's work = (1/15 + 1/20) = 7/60
    (A + B)'s 4 day's work = (7/60 * 4) = 7/15
    Therefore, Remaining work = (1 - 7/15) = 8/15
  3. Kim can do a work in 3 days while David can do the same work in 2 days. Both of them finish the work together and get Rs. 150. What is the share of Kim?
    A. Rs. 50
    B. Rs. 60
    C. Rs. 70
    D. Rs. 80
  4. B. Rs. 60
    Kim's wages : David's wages = Kim's 1 day work : David's 1 day work = 1/3 : 1/2 = 2:3
    Kim's share = 2/5 * 150 = Rs. 60
  5. Sakshi can do a piece of work in 20 days. Tanya is 25% more efficient than Sakshi. The number of days taken by Tanya to do the same piece of work is?
    A. 15 days
    B. 16 days
    C. 17 days
    D. 18 days
  6. B. 16 days
    Ratio of times taken by Sakshi and Tanys = 125:100 = 5:4
    Suppose Tanya takes x days to do the work.
    5:4 :: 20:x
    => x = 16 days
    Hence, Tanya takes 16 days to complete the work.
  7. 12 Men or 18 women can reap a field in 14 days. The number of days that 8 men and 16 women will take to reap it?
    A. 7 days
    B. 8 days
    C. 9 days
    D. 10 days
  8. C. 9 days
    12 men = 18 women or 1 man = 3/2 women
    Therefore 8 men + 16 women = (8 × 3/2 + 16) women i.e.., 28 women
    Now 18 women can reap the field in 14 days
    Therefore, 28 women can reap it in = 9 days
  9. A is thrice as efficient as B and is, therefore, able to finish a piece of work 10 days earlier than B. In how many days A and B will finish it together?
    A. 3 days
    B. 4 days
    C. 5 days
    D. 6 days
  10. C. 5 days
    WC = 3:1
    WT = 1:3
    x ------- 3x
    1/x – 1/3x = 1/10
    x = 20/3
    3/20 + 1/20 = 1/5 => 5 days
  11. A work which could be finished in 9 days was finished 3 days earlier after 10 more men joined. The number of men employed was?
    A. 18 men
    B. 20 men
    C. 22 men
    D. 24 men
  12. B. 20 men
    x ------- 9
    (x + 10) ---- 6
    x * 9 = (x + 10)6
    x = 20
  13. Tina can do a certain job in 12 hours. Working independently, Ann can do the same job in 9 hours. If Tina Works independently at the job for 8 hours and then Ann works independently, how many hours will it take Ann to complete the remainder of the jobs?
    A. 2/3 hr
    B. 3/4 hr
    C. 1 hr
    D. 3 hrs
  14. D. 3 hrs
    Work done by Tina in 1 hr = 1/12
    Work done by Tina in 8 hrs = 1/12*8 which is 2/3
    Now, the remaining work is 1/3 which is completed by Ann in 1/3*9 which is 3 hrs
  15. A can do a piece of work in 40 days; B can do the same in 30 days. A started alone but left the work after 10 days, then B worked at it for 10 days. C finished the remaining work in 10 days. C alone can do the whole work in?
    A. 16 days
    B. 24 days
    C. 32 days
    D. 40 days
  16. B. 24 days
    10/40 + 10/30 + 10/x = 1
    x = 24 days
  17. Ravi can do a piece of work in 30 days while Prakash can do it in 40 days. In how many days will they finish it together?
    A. 16 4/11 days
    B. 17 1/7 days
    C. 23 2/7 days
    D. 27 1/7 days
  18. B. 17 1/7 days
    1/30 + 1/40 = 7/120
    120/7 = 17 1/7 days
  19. Varma can read a book in k minutes. What part of the book can he read in 8 minutes? Given (k>8)
    A. k+8
    B. 8/k
    C. k/8
    D. (k-8)/k
  20. B. 8/k
    Part of the book he can read in 1 minute = 1/k
    Part of the book he can read in 8 minutes = 8/k