The average of seven numbers is 18. The average of first three numbers is 14 and the average of last three numbers is 16. What is the middle number?
Pick: A) 27 B) 29 C) 36 D) 34 E) 35
The total of seven numbers = 7X18 = 126   The total of first 3 and last 3 numbers is = 3 X 14+3 X 16 = 90   So, the middle number is  (126 - 90 )= 
<gadget id="calculator"> (126 - 90 )</gadget>
<output>36</output>
36   36
<result>C</result>
The average of seven numbers is 18. The average of first three numbers is 14 and the average of last three numbers is 16. What is the middle number?