A is as efficient as B and C together. Working together A and B can complete a work in 36 days and C alone can complete it in 60 days. A and C work together for 10 days. B alone will complete the remaining work in:

\[\begin{array}{*{20}{c}} {}&A&:&{B + C}&{}&{} \\ {{\text{Efficiency}} \to }&{{1_{ \times 4}}}&:&{{1_{ \times 4}}}& \Rightarrow &{{2_{ \times 4}}} \\ {}&{A + B}&:&C&{}&{} \\ {{\text{Days}} \to }&{36}&:&{60}&{}&{} \\ {{\text{Efficiency}} \to }&5&:&3& \Rightarrow &8 \\ {{\text{Efficiency}} \to }&A&:&B&:&C \\ {}&4&:&1&:&3 \end{array}\]
$$\eqalign{ & {\text{Total work}} = 3 \times 60 = 180 \cr & \left( {A + C} \right) \times 10 + B \times x = 180 \cr & 7 \times 10 + 1 \times x = 180 \cr & x = 110{\text{ Days}} \cr} $$