The mean age of the students in a high school book club is 15.4 years. A 32-
year-old teacher joins the club. Which sentence is true?
O
A. The mean age is still 15.4 years.
B. The new mean age is 23.7 years.
C. The new mean age is less than 15.4 years.
D. The new mean age is greater than 15.4 years.
