The number of books read by four students in a book club last month were 10, 12, 15, and 13. This month, a new student joins the club and reads 18 books. Which of the following statements correctly compares the mean number of books read by the original four students to the mean number of books read by all five students?
The mean for the original four students is greater than the mean for all five students.
The mean for the original four students is less than the mean for all five students.
The means of both data sets are equal.
There is not enough information to compare the means.
