901. A and B can do a piece of work in 21 and 24 days respectively.They start the work together and after some days, A leaves and B completes the rest of the task in 9 days. After how many days did A leave??
A. 5
B. Â 6
C. Â 7
D. Â 8

902. A can do piece of work in 30 days while B can do it in 40 days. In how many days can A and B working together do it ??
A. 70 days
B. Â 120/7 days
C. Â 50 days
D. Â 45 days

903. A can do a certain job in 12 days. B is 60% more efficient than A. The number of days it takes for B to do the same piece of work, is:_________??
A. 12/6 days
B. Â 15/2 days
C. Â 23 days
D. Â 34 days

904. Two pipes P and Q can fill a cistern in 12 minutes and 16 minutes respectively. Â Simultaneously both the pipes are opened together, then after how much time Q should be closed so that the tank is full in 9 min ??
A. 2 min
B. Â 3 min
C. Â 4 min
D. Â 5 min

905. P, Q and R can complete a work in 24, 6 and 12 days respectively. The work will be completed in________days if all of them are working together.?
A. 2
B. Â 3 3â„7
C. Â 4 Â¼
D. Â 5

906. A work can be finished in 16 days by twenty women. The same work can be finished in fifteen days by sixteen men. The ratio between the capacity of a man and a woman is_________??
A. 1:3
B. Â 4:3
C. Â 2:3
D. Â 2:1

907. If 10 bulls can plough 20 identical fields in 3 days working 10 hours a day, then in how many days can 30 bulls plough 32 same identical fields working 8 hours a day??
A. 2
B. Â 8
C. Â 10
D. Â 12

908. A can lay a railway track between two given stations in 16 days and B can do the same job in 12 days. With help of C, they did the job in 4 days only. Then, C alone can do the job in_________??
A. 4
B. Â 9.6
C. Â 9
D. Â 10

909. Twelve men can do a work in twenty days while twenty women can finish the same work in sixteen days. Find the ratio between the capacity of a man and a woman.?
A. 3:4
B. Â 5:4
C. Â 4:3
D. Â 5:3

910. A and B can finish a piece of work in 20 days .B and C in 30 days and C and A in 40 days. In how many days will A alone finish the job??
A. 48
B. Â 34(2/7)
C. Â 44
D. Â 45