A can do piece of work in 30 days while B can do it in 40 days. In how many days can A and B working together do it?
Q1. A can do piece of work in 30 days while B can do it in 40 days. In how many days can A and B working together do it?
Answer: 120/7 days
Explanation: Combined rate = 1/30 + 1/40 = 7/120 per day. Days together = 120/7 days.