To determine the constant of proportionality from the data provided, we need to find the ratio of pages read to time in hours for each entry in the table. Ruth can read 15 pages in 30 minutes, which means she reads 30 pages in 1 hour. Thus, we can use this information to establish the relationship.
Let's find the ratio (constant of proportionality) for the provided entries by calculating the pages read per hour (pph).
-
For (12 hours, 15 pages):
- Ratio = 15 pages / 12 hours = 1.25 pages per hour.
-
For (1 hour, 30 pages):
- Ratio = 30 pages / 1 hour = 30 pages per hour.
-
For (112 hours, 45 pages):
- Ratio = 45 pages / 112 hours = 0.40179 pages per hour (approximately).
-
For (2 hours, 60 pages):
- Ratio = 60 pages / 2 hours = 30 pages per hour.
The constant of proportionality provides us with the relationship of how many pages are read per hour. From this, we can see that only the entries for 1 hour (30 pages) and 2 hours (60 pages) stand out with consistent ratios, where both are reading at a speed of 30 pages per hour.
Now, looking at the options provided, the correct answer corresponding to the ratio of pages read to time that maintains consistency is:
(1, 30)
This indicates that for 1 hour, she reads 30 pages, which agrees with her reading speed.
So, the final answer is: (1, 30).