Solution:
Given:
[tex]\begin{gathered} \mu=50000 \\ \sigma=5000 \end{gathered}[/tex]Using the Z-score formula;
[tex]Z=\frac{x-\mu}{\sigma}[/tex]when x = 40000
[tex]\begin{gathered} Z=\frac{40000-50000}{5000} \\ Z=\frac{-10000}{5000} \\ Z=-2 \end{gathered}[/tex]Therefore, the Z-score for the weekly income of 40000 is -2
when x = 55000
[tex]\begin{gathered} Z=\frac{55000-50000}{5000} \\ Z=\frac{5000}{5000} \\ Z=1 \end{gathered}[/tex]Therefore, the Z-score for the weekly income of 55000 is 1
