2009 AMC 8 Problems/Problem 21
Problem
Andy and Bethany have a rectangular array of numbers greater than zero with rows and columns. Andy adds the numbers in each row. The average of his sums is . Bethany adds the numbers in each column. The average of her sums is . Using only the answer choices given, What is the value of ?
Solution
First, note that . Solving for , we get
See Also
2009 AMC 8 (Problems • Answer Key • Resources) | ||
Preceded by Problem 20 |
Followed by Problem 22 | |
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