George does 3/5th of a piece of work in 9 days.He then calls in Paul and they finish the work in 4 days.How long would Paul take to do the work by himself?	Choose one
A) 10
B) 20
C) 30
D) 40
E) 50

Rationale: "9 day 3 / 5 1 day 1 / 15 remaing 1 - 3 / 5 = 2 / 5 both can do 2 / 5 work in 4 day one day work of both = 1 / 10 therfor paul would take 1 / 10 - 1 / 15 = 1 / 30 or 30 days answer : c"
Answer: C