The formula for Z-score is given as,
[tex]Z=\frac{X-\mu}{\sigma}[/tex]Given that
[tex]\begin{gathered} X=percent\text{ of fat calories=30} \\ \mu=\operatorname{mean}\text{ = 36} \\ \sigma=10 \end{gathered}[/tex]Therefore,
[tex]\begin{gathered} Z=\frac{30-36}{10}=\frac{-6}{10}=-0.6 \\ \therefore Z=-0.6 \end{gathered}[/tex]Hence,
[tex]\begin{gathered} Z=-0.6\approx-0.600(3\text{ decimal places)} \\ \therefore Z=-0.600 \end{gathered}[/tex]