The average of seven numbers is 20. The average of first three numbers is 14 and the average of last three numbers is 19. What is the middle number?  Options:  A) 27  B) 29  C) 31  D) 41  E) 35
The total of seven numbers = 7X20 = 140   The total of first 3 and last 3 numbers is = 3 X 14+3 X 19 = 99   So, the middle number is  (140 - 99 )= 
<gadget id="calculator"> (140 - 99 )</gadget>
<output>41</output>
41   41
<result>D</result>
The average of seven numbers is 20. The average of first three numbers is 14 and the average of last three numbers is 19. What is the middle number?