The test statistic, z, is computed as follows:
[tex]z=\frac{\bar{x}-\mu}{\frac{\sigma}{\sqrt[]{n}}}[/tex]
where:
x: sample mean
μ: population mean
σ: standard deviation
n: number of samples
Substituting with x = 89.7, μ = 84.9, σ = 13.9, and n = 61, we get:
[tex]\begin{gathered} z=\frac{\bar{89.7}-84.9}{\frac{13.9}{\sqrt[]{61}}} \\ z=2.697 \end{gathered}[/tex]
