**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