A and B together can do work in 20 days, B and and C and do the same work in 60 days. Who is the most efficient among A,B and C?

A and B can complete a work in 40 days, B and C in 60 days and A and C is 48 days. Who is the most efficient worker among A, B and C?

A and B can do a work in 20 days, B and C in 40 days and A and C in 30 days. Who is the most efficient among the the three perosn?

A and B together can do a work in 10 days. B and C together can do the same work in 6 days. A and C together can do the work in 12 days. Then A, B and C together can do the work in

A and B together can do a piece of work in 20 days, while B and C together can do the same work in 15 days. If A ,B and C together can finish this work in 10 days, then find the number of days in which B alone can finish the work.

A and B together can do a piece of work in 20 days, while B and C together can do the same work in 15 days. If A ,B and C together can finish this work in 10 days, then find the number of days in which B alone can finish the work.

A and B together can do a piece of work in 12 days; B and C can do it in 20 days while C and A can do it in 15 days. A, B and C all working together can do it in