The average of twelve numbers is 7. The average of first nine numbers is 6 and the average of last two numbers is 10. What is the middle number?	Choose the correct choice from the following answers:
A) A)9  B) B)10  C) C)12  D) D)7  E) E)13
The total of twelve numbers = 12X7 = 84   The total of first 9 and last 2 numbers is = 9 X 6+2 X 10 = 74   So, the middle number is  (84 - 74 )= 
<gadget id="calculator"> (84 - 74 )</gadget>
<output>10</output>
10   10
<result>B</result>
The average of twelve numbers is 7. The average of first nine numbers is 6 and the average of last two numbers is 10. What is the middle number?