The average age of 19 students in a group is 17 years. When teacher’s age is included to it, the average increases by one. What is the teacher’s age in years?  Choose the most appropriate option:
A) 36	B) 37	C) 38	D) cannot be determined	E) None of these
Age of the teacher = (20 × 18 – 19 × 17) years   = 37 years.   Answer 37
<result>B</result>
The average age of 19 students in a group is 17 years. When teacher’s age is included to it, the average increases by one. What is the teacher’s age in years?