A set of 10 new questions in each round Question: ( 1 of 10 ) If Robert can finish a work in 4 days and Bob can finish the same work in 6 days, then in how many days they both can finish the work working together? (A) 22/5 days or 2.4 days (B) 32/5 days or 3.4 days (C) 31/2 days or 3.5 days (D) 34/5 days or 3.8 days