A summary of transactions at a small bookstore is shown below:
| Magazine purchased | Magazine not purchased | Total | |
|---|---|---|---|
| Book purchased | 32 | 18 | 50 |
| Book not purchased | 13 | 7 | 20 |
| Total | 45 | 25 | 70 |
If a customer is picked at random, what is the probability that the customer did not purchase a book?
