Amrit is thrice as good a workman as Bhagat. Therefore Amrit is able to finish a piece of work in 50 days less than Bhagat. The time (in days) in which they can finish it working together is:

A

$$19\frac{5}{4}$$ days

B

$$15\frac{3}{4}$$ days

C

$$18\frac{3}{4}$$ days

D

$$17\frac{4}{3}$$ days