P alone can complete a job in 6 days. The work done by Q alone in one day is equal to one-fifth of the work done by P alone in one day. In how many days can the work be completed if P and Q work together?  Pick one:
A) 1 B) 2 C) 3 D) 4 E) 5
P's rate is 1/6   Q's rate is 1/30   The combined rate is 1/6 + 1/30 = 1/5   If they work together, the job will take 5 days.   The answer is 5.
<result>E</result>
P alone can complete a job in 6 days. The work done by Q alone in one day is equal to one-fifth of the work done by P alone in one day. In how many days can the work be completed if P and Q work together?