To find out how many yards of fabric Joanne will use for each costume, you need to divide the total amount of fabric she has by the number of costumes she is making.
The total amount of fabric Joanne has is \( 13 \frac{1}{4} \) yards, and she is making \( 4.5 \) costumes.
First, convert \( 13 \frac{1}{4} \) to an improper fraction: \[ 13 \frac{1}{4} = \frac{13 \times 4 + 1}{4} = \frac{52 + 1}{4} = \frac{53}{4} \text{ yards} \]
Next, you can perform the division: \[ \text{Fabric per costume} = \frac{\text{Total fabric}}{\text{Number of costumes}} = \frac{\frac{53}{4}}{4.5} \]
To make this division easier, convert \( 4.5 \) to a fraction: \[ 4.5 = \frac{9}{2} \]
Now, perform the division: \[ \frac{\frac{53}{4}}{\frac{9}{2}} = \frac{53}{4} \times \frac{2}{9} = \frac{53 \times 2}{4 \times 9} = \frac{106}{36} \]
Now, simplify the fraction \( \frac{106}{36} \):
- Divide the numerator and denominator by 2: \[ \frac{106 ÷ 2}{36 ÷ 2} = \frac{53}{18} \]
Thus, the amount of fabric Joanne will use for each costume is \( \frac{53}{18} \) yards.
To summarize, the operation you will use is division.