Answer:
1) At least one (the 11th) student is 23 (years old), <u>Must be true</u>
2) Some students are younger than 15 <u>Could be true</u>
Step-by-step explanation:
1) The given parameters are;
The number of student in the class = 21
The median age of the student = 23
The age of the oldest student = 29
Therefore, given that the median age = The age of the (n + 1)/2 th student
Where;
n = The number of student in the class = 21
∴ The median age = The age of the (21 + 1)/2 th = 11 th student, when the age of the students are arranged in increasing order, therefore, we have;
At least one (the 11th) student is 23 (years old), <u>Must be true</u>
2) Given that there are 10 students with ages equal to or lower than the median age, and the difference between the median age and the age of the oldest student = 29 - 23 = 6 years, we have;
Some students are younger than 15 <u>Could be true</u>