Abel can complete a work in 10 days, Ben in 14 days and Carla in 15 days. All of them began the work together, but Abel had to leave after 2 days and Ben 3 days before the completion of the work. How long did the work last?  Select.
A) 6	B) 7	C) 7 10/29	D) 9	E) 10
Abel in the 2 days that he worked completed 1/5 of the job = 4/5 remains   Then if Ben had to leave 3 days before the completion, this means that Carla had to work alone for these 3 days in which she completed 1/5 of the job.   Now together, Ben and 7 10/29arla completed the job in (1/14 + 1/15)(t) = 3/5   29/210 (t) = 3/5 ---&gt; t = 126/29   Therefore, these 4 10/29 days worked plus the 3 days that 7 10/29arla had to work by herself add to 7 10/29 days   Answer: 7 10/29
<result>C</result>
Abel can complete a work in 10 days, Ben in 14 days and Carla in 15 days. All of them began the work together, but Abel had to leave after 2 days and Ben 3 days before the completion of the work. How long did the work last?