'A' is 3 times as good a workman has 'B' and therefore is able to complete a job in 35 days less than 'B'. In how many days will they finish 40% of the work, working together?

A

$$3\frac{1}{2}$$

B

$$4\frac{2}{5}$$

C

$$5\frac{2}{5}$$

D

$$5\frac{1}{2}$$