Two pipes can fill a tank in 10 hrs. and 12 hrs. respectively while a third pipe empties the full tank in 20 hrs.  If all the three pipes operate together , in how much time the tank will be filled ? 

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A, B and C can do a piece of work in 20, 30 and 60 days respectively. In how many days can A do the work if he is assisted by B and C on every Third day ?

A. 12 days B. 15 days C. 16 days D. 18 days...

A alone can finish a work in 10 days and B alone can do it in 15 days. If they work together and finish, then out of a total wages of Rs.75. A will get:___________?

A. 35 Rs. B. 40 Rs. C. 45 Rs. D. None of these...

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. 8 C. 10 D. 12...

Machine P can print one lakh books in 8 hours. Machine Q can print the same number of books in 10 hours while machine R can print the same in 12 hours. All the machines started printing at 9 A.M. Machine P is stopped at 11 A.M. and the remaining two machines complete work. Approximately at what time will the printing of one lakh books be completed?

A. 3 pm B. 2 pm C. 1:00 pm D. 11 am...

P takes twice as much time as Q or thrice as much time as R to finish a piece of work. They can finish the work in 2 days if work together. How much time will Q take to do the work alone?

A. 7 B. 8 C. 9 D. 6 Let P takes x days to complete the work Then Q takes x/2 days and R takes x/3 days to finish the work Amount of work P does in 1 day = 1/x Amount of work Q does in 1 day = 2/x Amount of work R does in 1 day … P takes twice as much time as Q or thrice as much time as R to finish a piece of work. They can finish...