P is four times as fast as Q and working together, they can complete a work in 8 days. In how many days can Q alone complete the work?	Choose the correct choice from the following choices.
A) 35 days	B) 15 days	C) 10 days	D) 25 days	E) 18 days
P = 4Q   P + Q = 4Q + Q = 5Q   These 5Q people can do the work in 8 days, which means Q can do the work in 40 days.   Hence, P can do the work in 10 days.   ANSWER:10 days
<result>C</result>
P is four times as fast as Q and working together, they can complete a work in 8 days. In how many days can Q alone complete the work?