The average age of 44 students in a group is 12 years. When teacher’s age is included to it, the average increases by one. What is the teacher’s age in years?
Choose the correct choice from the following answers:
A) cannot be determined	B) None of these	C) 55	D) 56	E) 57
Age of the teacher = (45 × 13 – 44 × 12) years   = 57 years.   Answer 57
<result>E</result>
The average age of 44 students in a group is 12 years. When teacher’s age is included to it, the average increases by one. What is the teacher’s age in years?