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:
![score=100\%-4.5\%=1-0.045=0.955](https://img.qammunity.org/2023/formulas/mathematics/high-school/o2xa0gyqkgzrfy1vfbrkrcogysfm520uui.png)
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:
![z=(x-\mu)/(\sigma)](https://img.qammunity.org/2023/formulas/mathematics/college/h06hsre30elxbqnbdkqzw5pbp57988qa0r.png)
Where μ is the mean and σ is the standard deviation.
So, using the given values, we have:
![\begin{gathered} 1.695=(x-28)/(0.34) \\ x-28=1.695\cdot0.34 \\ x-28=0.5763 \\ x=28.5763 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/high-school/y75x9h2s3cvvyjauhricvu08hfjb5pl8l8.png)
Rounding to two decimal places, we have a weight of 28.58 ounces.