Ram, who is half as efficient as Krish, will take 27 days to complete a task if he worked alone. If Ram and Krish worked together, how long will they take to complete the task?  Choose one
A) 16 days	B) 12 days	C) 9 days	D) 6 days	E) 18 days

Rationale: number of days taken by ram to complete task = 27 since ram is half as efficient as krish , amount of work done by krish in 1 day = amount of work done by ram in 2 days if total work done by ram in 27 days is 27 w amount of work done by ram in 1 day = w amount of work done by krish in 1 day = 2 w total amount of work done by krish and ram in a day = 3 w total amount of time needed by krish and ram to complete task = 27 w / 3 w = 9 days answer c
Answer: C