A set of 10 new questions in each round Question: ( 1 of 10 ) If Mark can finish the work in 30 days and Jacob can finish the same work in 33 days, then in how many days both can finish the work together? (A) 63 days (B) 15 5/7 days or 15.714 days (C) 30 5/7 days or 30.714 days (D) 31.5 days