In order to find the maximum weight, first we need to find the value of z that corresponds to the upper 4.5%.
To do so, let's find the value of z with a score of:
[tex]score=100\%-4.5\%=1-0.045=0.955[/tex]Looking at the z-table, the value of z for a score of 0.955 is equal to 1.695.
Now, to find the maximum weight x, we can use the formula below:
[tex]z=\frac{x-\mu}{\sigma}[/tex]Where μ is the mean and σ is the standard deviation.
So, using the given values, we have:
[tex]\begin{gathered} 1.695=\frac{x-28}{0.34} \\ x-28=1.695\cdot0.34 \\ x-28=0.5763 \\ x=28.5763 \end{gathered}[/tex]Rounding to two decimal places, we have a weight of 28.58 ounces.