[tex]\bf \begin{array}{ccll}
\stackrel{lbs}{earth}&\stackrel{lbs}{moon}\\
\text{\textemdash\textemdash\textemdash}&\text{\textemdash\textemdash\textemdash}\\
1&0.167\\
180&x
\end{array}\implies \cfrac{1}{180}=\cfrac{0.167}{x}\implies x=\cfrac{180\cdot 0.167}{1}[/tex]