The average age of a class of 25 students is 19 years. The average increased by 2 when the teacher's age also included. What is the age of the teacher?
Options.
A) 40 years  B) 41 years  C) 47 years  D) 43 years  E) 44 years
If age of the teacher was 19, average would not have changed.   Since average increased by 2,   Age of the teacher=25+22×1=47   ANSWER:47 years
<result>C</result>
The average age of a class of 25 students is 19 years. The average increased by 2 when the teacher's age also included. What is the age of the teacher?