The average age of a class of 34 students and a teacher reduces by 0.5 years, if the teacher is excluded. The initial average of the class including teacher is 16 years. Find the age of the teacher.

The teacher is 33 years old.

With the teacher, 35 people average 16, so total = 35 x 16 = 560.

Without the teacher, 34 students average 16 - 0.5 = 15.5.

Their total = 34 x 15.5 = 527.

Teacher's age = 560 - 527 = 33 years.