Multiple choice

Average age of 10 students in a class is x. If the age of the teacher is included, the average age becomes z. What is the age of the teacher?

  1. 11z - 10x

  2. 10z - 11x

  3. 10(z - x)

  4. 11(z - x)

  5. e

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Total age of 10 students = 10x. Total age with teacher = 11z. Teacher's age = 11z - 10x.

AI explanation

The initial total age of the 10 students is 10x. When the teacher is included, the total age of all 11 people becomes 11z. Therefore, the teacher's age is the new total minus the students' total, which evaluates to 11z minus 10x.