To find the constant of proportionality, we need to determine the ratio of the number of rolls of paper towels to the number of cases ordered for each entry in the table.
- For 1 case: \( \frac{12 \text{ rolls}}{1 \text{ case}} = 12 \)
- For 3 cases: \( \frac{36 \text{ rolls}}{3 \text{ cases}} = 12 \)
- For 5 cases: \( \frac{60 \text{ rolls}}{5 \text{ cases}} = 12 \)
- For 10 cases: \( \frac{120 \text{ rolls}}{10 \text{ cases}} = 12 \)
The constant of proportionality is 12, and it appears in each ratio.
So, you can represent the constant of proportionality as the ordered pair of the number of cases and rolls that shows this ratio. Let's consider the first entry:
(1, 12)
Therefore, the answer is:
(1, 12)