A set of 10 new questions in each round Question: ( 1 of 10 ) Susan can finish a work in 18 days. Sarah can finish the same work in 23 days while Karen can finish the work in 28 days. How long will it take to finish it if they work together? (A) 17.25 days (B) 7 329/781 days or 7.421 days (C) 14 329/781 days or 14.421 days (D) 23 days