1/20 + 1/40 = 3/40
40/7 = 5 7/9 days
Ravi can do a piece of work in 20 days while Prakash can do it in 40 days. In how many days will they finish it together?
Options:
A) 5 7/9 days
B) 6 7/9 days
C) 5 1/9 days
D) 5 7/2 days
E) 4 7/9 days