Mean Books Purchased by Genre

A local bookstore conducted a survey to analyze the reading preferences of its customers. They found the following number of books purchased across various genres last month:

• Fiction: 50
• Non-Fiction: 30
• Mystery: 20
• Science Fiction: 10

What is the mean number of books purchased per genre? Calculate the mean using the formula:

Mean = \f\frac{\text{Total number of items}}{\text{Number of categories}}