Ruth can read 15 pages in 30 minutes. She decides to create a table to keep track of her progress. From the data provided, at what ratio is the unit rate (constant of proportionality) represented?
The unit rate is the number of pages read per minute. From the data provided, Ruth reads 15 pages in 30 minutes. Therefore, the unit rate is 15 pages / 30 minutes = 1/2, or 0.5 pages per minute.
The ratio at which the unit rate is represented is 0.5 pages per minute.