A and B can do a work in 8 days, B and C can do the same work in 12 days. A, B and C together can finish it in 6 days. A and C together will do it in? Choices
A) 7  B) 6  C) 8  D) 9  E) 5
(A + B + C)'s 1 day work = 1/6;   (A + B)'s 1 day work = 1/8   (B + C)'s 1 day work = 1/12   (A + C)'s 1 day work = (2 * 1/6) - (1/8 + 1/12)   = (1/3 - 5/24) = 1/8   So, A and C together will do the work in 8 days.   Answer:8
<result>C</result>
A and B can do a work in 8 days, B and C can do the same work in 12 days. A, B and C together can finish it in 6 days. A and C together will do it in?