When a system is taken from state $‘a^{\prime }$ to state $‘b^{\prime }$ along the path $‘ac{b}^{\prime }$, it is found that a quantity of heat $Q=200\text{J}$ is absorbed by the system and a work $W=80\text{J}$ is done by it. Along the path $‘ad{b}^{\prime },Q=144\text{J}$. The work done along the path $‘ad{b}^{\prime }$ is