2005 AMC 12A Problem 5
Below is the professionally curated solution for Problem 5 of the 2005 AMC 12A, from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 2005 AMC 12A solutions, or check the answer key.
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Difficulty rating: 1020
5.
The average (mean) of numbers is and the average of other numbers is What is the average of all numbers?
Solution:
The total of all numbers is
The average is
Thus, the correct answer is B.
Problem 5 in Other Years
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