Three classes A, B and C have 24, 40 and 32 students, and the average ages of their students are 22, 26 and 29 years respectively. What is the average age of all the students of the three classes?
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → 26 years
The average of all three classes together is the sum of the ages of all the students divided by the total number of students.
Class A: \(24\times22=528\) years
Class B: \(40\times26=1040\) years
Class C: \(32\times29=928\) years
Total \(=528+1040+928=2496\) years for \(24+40+32=96\) students
\(\displaystyle \text{Average}=\frac{2496}{96}=26\) years
The average age of all the students is 26 years.