The frequency table shows the number of books read by 20 students in a month.
| Number of Books | Frequency |
|---|---|
| 0 | 2 |
| 1 | 5 |
| 2 | 7 |
| 3 | 4 |
| 4 | 2 |
If a new student joins the group and reports reading 1 book, which statement describes how the mean and median number of books change for the entire group?
The mean increases, and the median stays the same.
The mean decreases, and the median stays the same.
The mean increases, and the median increases.
The mean decreases, and the median decreases.
