The following table shows the number of books read by each student in a class over a month. Calculate the mean number of books read by the students.

| Student | Number of Books Read |
|---------|-----------------------|
| A       | 4                     |
| B       | 7                     |
| C       | 5                     |
| D       | 3                     |
| E       | 6                     |
| F       | 8                     |
| G       | 2                     |
| H       | 9                     |
| I       | 5                     |
| J       | 6                     | Let's think step by step and output the final answer within \boxed{}.
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