A and B can do a piece of work in 2 days. With the help of C they finish the work in 1 days. C alone can do that piece of work in? Pick
A) 1.5 days	B) 4 days	C) 3 days	D) 1 day	E) 2 days

Rationale: c = 1 / 1 – 1 / 2 = 1 / 2 = > 2 days answer : e
Answer: E