The average age of 12 students is 14 years. If the age of the teacher is also included, the average becomes 15 years. What is the age of the teacher?

23 years 25 years 27 years 28 years

27 years

Sum of age of 12 students = 12 × 14 = 168 years After adding age of teacher Sum of Age of 12 students + 1 teacher = 13 × 15 = 195 years Age of teacher = 195 - 168 = 27 years