Question: The average of seven numbers is 18. The average of first three numbers is 16 and the average of last three numbers is 20. What is the middle number?\nOptions:\n(A) 20\n(B) 22\n(C) 25\n(D) 18\n(E) 24 Random thoughts:
User
The total of seven numbers = 7X18 = 126\nThe total of first 3 and last 3 numbers is = 3 X 16+3 X 20 = 108\nSo, the middle number is (126 - 108 ) = 18 The final answer: (D).
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