Two pipes A and B individually can fill a tank in 15 hours, and 12 hours respectively, and C can empty the full tank in 4 hour. If all three pipes are open at 8, 9, and 11 am respectively. At what time tank will be completely empty?

A pump can fill a tank with water in 1 hour. Because of a leak, it took \(1{1\over3}\) hours to fill the tank. In how many hours can the leak alone drain all the water of the tank when it is full?

15 persons working 6 hours per day earn Rs. 900. How much money will 20 persons earn, working 10 hours per day?

Sachin alone can complete a piece of work for Rs. 8,500 in \(8\frac{1}{2}\) days. But with the help of Vishnu, the work is completed in 6 days. The share to be paid to Vishnu is: