A can do a piece of work in 14 days. B is 40% more efficient than A. In how many days can B complete that work?
Let us first calculate the one day work of B. One day work of A is given as $1/14$. If B is 40% efficient, then one day work of B is $1/14$ × $140/100$ = $1/10$. Which gives 10 days as the answer.