A can finish a work in 18 days and B can do the same work in half the time taken by A. Then, working together, what part of the same work they can finish in a day?
A can complete the work in 18 days
so, A’s 1-day work = 1/18
B can do the same work in half the time
So, B can complete the whole work in 9 days
Hence, B’s 1-day work = 1/9
If both start working together, in one day they will complete:
Thus, (A + B)’s combined 1-day work = (1/18)+ (1/9) => 3/18 => 1/6
Hence 1/6 of the work will be completed in a day, if they both work together.