Given:
The total cost of the clothing, C=$765.47.
The shipping weight, W=29 lb. 12 oz.
The sales tax rate, R=9.0%.
The shipping weight in lb is,
[tex]\begin{gathered} W=29\text{ lb+0.12 oz} \\ =29\text{ lb+0}.12\text{ oz}\times\frac{\frac{1}{16}\text{ lb}}{1\text{ oz}} \\ =29\text{ lb+0.0075 lb} \\ =29.0075\text{ lb} \end{gathered}[/tex]Given, shipping charges are $5.94 for 15 lb. For every additional lb. or fraction of a lb. above 15 lbs., the shipping charge is $0.12 per lb.
The shipping weight above 15 lb is,
[tex]\begin{gathered} w=W-15 \\ =29.0075-15 \\ =14.0075\text{ lb} \end{gathered}[/tex]Now, the total shipping charge for 29.0075 lb is,
[tex]\begin{gathered} S=5.94+0.12w \\ =5.94+0.12\times14.0075 \\ =5.94+1.6809 \\ =7.6209\text{ dollars} \end{gathered}[/tex]Now, the pre tax cost of the item is,
[tex]\begin{gathered} c=C+S \\ =765.47+7.6209 \\ =773.0909 \end{gathered}[/tex]Now, the sales tax of the item is,
[tex]\begin{gathered} ST=\frac{R}{100}\times c \\ =\frac{9}{100}\times773.0909 \\ =69.578 \end{gathered}[/tex]Now, the total cost of the order is,
[tex]\begin{gathered} T=C+ST \\ =773.0909+69.578 \\ =842.67 \end{gathered}[/tex]So, the total cost of the order can be $842.10.