3 1/2 as a improper fraction is:
[tex]3\frac{1}{2}=\frac{3\cdot2+1}{2}=\frac{7}{2}\text{ ft}[/tex]Given that he buys 5 sections, the total length of fabric is:
[tex]5\cdot\frac{7}{2}=\frac{5\cdot7}{2}=\frac{35}{2}\text{ ft}[/tex]3 feet are equivalent to 1 yard. Converting 35/2 ft into yards:
[tex]\frac{35}{2}\text{ ft}\cdot\frac{1\text{ yd}}{3\text{ ft}}=\frac{35}{2\cdot3}=\frac{35}{6}\text{ yd}[/tex]16 1/2 as a improper fraction is:
[tex]16\frac{1}{2}=\frac{16\cdot2+1}{2}=\frac{33}{2}\text{ yd}[/tex]There is no leftover because 33/2 yd (the amount of fabric needed) is greater than 35/6 yd (the amount of fabric purchased)