A can do a piece of work in 3 hours; B and C together can do it in 2 hours, which A and B together can do it in 2 hours. How long will C alone take to do it?
Select the correct option
A) 2 hours	B) 5 hours	C) 6 hours	D) 4 hours	E) 3 hours

Rationale: "a ' s 1 hour work = 1 / 3 ; ( b + c ) ' s 1 hour work = 1 / 2 ; ( a + b ) ' s 1 hour work = 1 / 2 ( a + b + c ) ' s 1 hour work = ( 1 / 3 + 1 / 2 ) = 5 / 6 c ' s 1 hour work = ( 5 / 6 - 1 / 2 ) = 1 / 3 c alone will take 3 hours to do the work . answer : e"
Answer: E