A can do a work in 10 days and B can do the same work in 15 days. In how many days will they finish the work if they work together?
Q1. A can do a work in 10 days and B can do the same work in 15 days. In how many days will they finish the work if they work together?
Answer: 6 days
Explanation: A's 1 day's work = 1 / 10, B's 1 day's work = 1 / 15. Together, their 1 day's work = 1 / 10 + 1 / 15 = (3 + 2) / 30 = 1 / 6. So, they will finish the work in 6 days.