9. P and can do a given piece of work in 8 days: Q and R can do the sa

1.	9. P and can do a given piece of work in 8 days: Q and R can do the same work in 12 days and Pcomplete it in 6 days. In how many days can P and R finish it?
Answer» In one day amount of work done by P and Q = 1/8 In one day amount of work done by Q and R = 1/12 In one day amount of work done by P, Q and R = 1/6 Then, In one day amount of work done R = 1/6 - 1/8= (4-3)/24 = 1/24 In one day amount of work done by P = 1/6 - 1/12= (2-1)/12 = 1/12 Therefore, amount of work done by done P and R in one day = 1/12 + 1/24 = (2 +1)/24= 3/24 = 1/8 P and R can finish work in 8 days

9. P and can do a given piece of work in 8 days: Q and R can do the same work in 12 days and Pcomplete it in 6 days. In how many days can P and R finish it?

Answer»

In one day amount of work done by P and Q = 1/8

In one day amount of work done by Q and R = 1/12

In one day amount of work done by P, Q and R = 1/6

Then, In one day amount of work done R = 1/6 - 1/8= (4-3)/24 = 1/24

In one day amount of work done by P = 1/6 - 1/12= (2-1)/12 = 1/12

Therefore, amount of work done by done P and R in one day = 1/12 + 1/24 = (2 +1)/24= 3/24 = 1/8

P and R can finish work in 8 days