ANSWER
[tex]\begin{equation*} 40\% \end{equation*}[/tex]EXPLANATION
The efficiency of the pulley system is given by:
[tex]E=\frac{Output\text{ }work}{Input\text{ }work}*100[/tex]Hence, the efficiency of the pulley system is:
[tex]\begin{gathered} E=\frac{80}{200}*100 \\ E=40\% \end{gathered}[/tex]That is the answer.
