A set of 10 new questions in each round Question: ( 1 of 10 ) Richard can finish a work in 13 days. Joseph can finish the same work in 14 days while Thomas can finish the work in 15 days. How long will it take to finish it if they work together? (A) 4 382/587 days or 4.651 days (B) 10.5 days (C) 8 382/587 days or 8.651 days (D) 14 days