A can do a piece of work in 40 days and B in 45 days. They work together for 10 days and then B goes away. In how many days will A finish the remaining work?
Given,
A can do a piece of work in 40 days
B can do it in = 45 days
A’s 1 day work = 
B’s 1 day work = 
(A+B)’s 1 day work together = 
A+B’s 10 day work = 
Remaining work = 
∴ Remaining work will be done by A = 
days.
13