Total fabric available = 40 yards
Number of dresses to be made = 8
Number of scarves to be made = 14
Amount of fabric used to make one dress = [tex]3\frac{1}{2}=\frac{7}{2}[/tex]
So fabric used to make 8 dresses = [tex]8\times\frac{7}{2}=28[/tex] yards
Amount of fabric used to make 1 scarf = [tex]\frac{3}{4}[/tex]
Fabric used to make 14 scarves = [tex]14\times\frac{3}{4}=10.5[/tex] or [tex]10\frac{1}{2}=\frac{21}{2}[/tex] yards
Hence, total fabric used to make dresses and scarves = [tex]28+\frac{21}{2}=\frac{56+21}{2}=\frac{77}{2}[/tex]
Leftover fabric = [tex]40-\frac{77}{2}=\frac{80-77}{2}=\frac{3}{2}[/tex] yards
[tex]\frac{1}{4}[/tex] yards is used to make = 1 sash
1 yard is used to make = [tex]\frac{1}{\frac{1}{4}}[/tex] sach
[tex]\frac{3}{2}[/tex] yards is used to make = [tex]4\times\frac{3}{2}=6[/tex]
Hence, 6 sashes can be made.