2004 AMC 8 Problems/Problem 9
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Problem
The average of the five numbers in a list is . The average of the first two
numbers is
. What is the average of the last three numbers?
Solution
Let the numbers be
, and
. Thus
and
. Since
,
. Substituting back into our original equation, we have
and
. Dividing by
gives the average of
.
See Also
2004 AMC 8 (Problems • Answer Key • Resources) | ||
Preceded by Problem 8 |
Followed by Problem 10 | |
1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 • 11 • 12 • 13 • 14 • 15 • 16 • 17 • 18 • 19 • 20 • 21 • 22 • 23 • 24 • 25 | ||
All AJHSME/AMC 8 Problems and Solutions |
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