John can do a piece of work alone in 20 days, while Ravi can do the same piece of work alone in 28 days. In how many days can the duo complete the same work if they work together?

A

$$11\frac{1}{3}$$

B

$$12\frac{2}{3}$$

C

$$11\frac{2}{3}$$

D

$$12\frac{1}{3}$$