Three taps P, Q and R can fill a tank in 12 hrs, 15 hrs and 20 hrs respectively. If P is open all the time and Q and R are open for one hour each alternately, starting with Q, then the tank will be full in how many hours ?

G is twice as fast as S in doing work. If G can do a work in 30 days less than S, how many days will they take to complete the work together?

X can complete 5/7 part of a work in 10 days and Y can complete 3/4 part of the same work in 9 days. In how many days will both complete 13/21 part  of the total work?

P can do a work in 10 days. Q can do the same work in 15 days. If they work together for 5 days, how much of the work will they complete?

P can make a table in 16 days while Q can make it in 20 days. Q started the work and did that work for 5 days. In how many days P can complete the remaining work?

S and T can finish a work in 50 days. They worked together for 20 days and then left. How much of the work is left?

Type 1 workers are 2.5 times as efficient as type 2 workers. Twelve Type 1 workers can complete a task in 10 days. How many days would it have taken 4 Type 1 and 15 Type 2 workers to do the same work?

P, Q and R alone can complete a work in 12, 15 and 20 days respectively. In how many days will they together complete the same work?

A, B and C can complete the work in 4, 5 and 6 hours respectively. If they all work together and receive Rs. 777 as wages then find the share of A.