first off, let's convert the mixed fractions to "improper fractions".
6 and 1/2 sections, each of 4 and 1/3 feet? is just their product.
[tex]\bf \stackrel{mixed}{4\frac{1}{3}}\implies \cfrac{4\cdot 3+1}{3}\implies \stackrel{improper}{\cfrac{13}{3}}
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\stackrel{mixed}{6\frac{1}{2}}\implies \cfrac{6\cdot 2+1}{2}\implies \stackrel{improper}{\cfrac{13}{2}}\\\\
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\cfrac{13}{3}\cdot \cfrac{13}{2}\implies \cfrac{13\cdot 13}{3\cdot 2}\implies \cfrac{169}{6}\implies 28\frac{1}{6}[/tex]
