Multiple choice

The average age of a class of 44 students is 15.5 years. When the teacher's age is factored in, the average age of the class rises to 16 years. What is the age of the teacher?

  1. 43

  2. 40

  3. 36

  4. 38
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Total age of 44 students is 44 * 15.5 = 682. With the teacher, there are 45 people with an average of 16, so total age is 45 * 16 = 720. The teacher's age is 720 - 682 = 38.

AI explanation

The total age of the 44 students is 44 times 15.5, which equals 682 years. When the teacher is included, the total age for 45 people becomes 45 times 16, giving 720 years. The teacher's age is the difference between 720 and 682, which is 38 years.

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