A proportional relationship between time and books is one where the ratio of books sold to time is constant. Looking at the data provided, Store A sells 11 books after 1 day and 33 books after 3 days, demonstrating a proportional relationship.
A proportional relationship between time and books is one where the ratio of books sold to time is constant. In other words, if we double the time, we should also double the number of books sold. Looking at the data provided, we can see that after 1 day, Store A sells 11 books and after 3 days, they sell 33 books. Similarly, after 1 day, Store B sells 5 books and after 3 days, they sell 15 books. If we calculate the ratio of books sold to time for both stores, we get:
Store A: 11/1 = 11 books per day
Store B: 5/1 = 5 books per day
Store A: 33/3 = 11 books per day
Store B: 15/3 = 5 books per day
As we can see, the ratio of books sold to time is the same for both stores. Therefore, the book sale that represents a proportional relationship between time and books is when Store A sells 11 books after 1 day and 33 books after 3 days.