The average of seven numbers is 18. The average of first three numbers is 12 and the average of last three numbers is 19. What is the middle number?
Pick:
A) 25	B) 27	C) 29	D) 33	E) 34
The total of seven numbers = 7X18 = 126   The total of first 3 and last 3 numbers is = 3 X 12+3 X 19 = 99   So, the middle number is  (126 - 93 )= 
<gadget id="calculator"> (126 - 93 )</gadget>
<output>33</output>
33   33
<result>D</result>
The average of seven numbers is 18. The average of first three numbers is 12 and the average of last three numbers is 19. What is the middle number?