The average student age of a certain class which has 45 students is 14. If one student aged 15 go to another class and the age of the class teacher is included the average changes to 14.66. What is the age of class teacher?  Answers
A) 30
B) 35
C) 38
D) 40
E) 45
Sum of ages of class before replacement= 45x14=630   Sum of ages of class without teacher= 630-15= 
<gadget id="calculator">630-15</gadget>
<output>615</output>
615   Sum of ages of class after replacement=45x14.66=660   Age of teacher=660-615= 
<gadget id="calculator">660-615</gadget>
<output>45</output>
45   Answer: 45
<result>E</result>
The average student age of a certain class which has 45 students is 14. If one student aged 15 go to another class and the age of the class teacher is included the average changes to 14.66. What is the age of class teacher?