To determine the constant of proportionality from the table provided, we look at the ratio of pages read to time in hours.
Based on the data:
- At 1/2 hour (30 minutes), Ruth reads 15 pages.
- At 1 hour, she reads 30 pages.
- At 1 1/2 hours, she reads 45 pages.
- At 2 hours, she reads 60 pages.
The relationship between pages read and time in hours can be expressed as:
- For 1/2 hour: \( \frac{15 \text{ pages}}{1/2 \text{ hour}} = 30 \text{ pages per hour} \)
- For 1 hour: \( \frac{30 \text{ pages}}{1 \text{ hour}} = 30 \text{ pages per hour} \)
- For 1 1/2 hours: \( \frac{45 \text{ pages}}{1.5 \text{ hours}} = 30 \text{ pages per hour} \)
- For 2 hours: \( \frac{60 \text{ pages}}{2 \text{ hours}} = 30 \text{ pages per hour} \)
The constant of proportionality is 30 pages per hour, which corresponds to a ratio of (1, 30) since for every 1 hour, she reads 30 pages.
Thus, the correct response is:
(1, 30)