P, Q, and R can complete a work in 20, 25, and 15 days respectively. They all start working together. After 4 days, P and Q leave the work. After 2 mo...
Question
P, Q, and R can complete a work in 20, 25, and 15 days respectively. They all start working together. After 4 days, P and Q leave the work. After 2 more days, R also leaves, and P resumes working alone. After 3 days, P leaves and Q joins to complete the remaining work. What is the total time taken to finish the entire work?