Answer
Beth needs $\frac{17}{8}$ yards of fabric.
Work Step by Step
A 12'' round pillow needs $\frac{1}{2}$ yard of fabric
An 18'' square pillow needs $\frac{3}{4}$ yard of fabric
A 12'' $\times$ 16'' rectangular pillow needs $\frac{7}{8}$ yards of fabric
To find how much fabric is needed, we add:
$\frac{1}{2}$ + $\frac{3}{4}$ + $\frac{7}{8}$ =
As we can see, the LCD is 8, so we need to make all the denominators 8:
$\frac{1 \times 4}{2 \times 4}$ + $\frac{3 \times 2}{4 \times 2}$ + $\frac{7}{8}$ =
$\frac{4}{8}$ + $\frac{6}{8}$ + $\frac{7}{8}$ =
We add the numerators when the denominators are the same.
$\frac{4 + 6 + 7}{8}$ = $\frac{17}{8}$ yards of fabric.
