MathDB
Problems
Contests
National and Regional Contests
USA Contests
MAA AMC
AMC 12/AHSME
1999 AMC 12/AHSME
3
Arithmetic Mean
Arithmetic Mean
Source:
January 19, 2006
arithmetic mean
Problem Statement
The number halfway between
1
8
\frac {1}{8}
8
1
and
1
10
\displaystyle \frac {1}{10}
10
1
is
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A
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1
80
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B
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1
40
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C
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1
18
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D
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1
9
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E
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9
80
<span class='latex-bold'>(A)</span>\ \frac {1}{80} \qquad <span class='latex-bold'>(B)</span>\ \frac {1}{40} \qquad <span class='latex-bold'>(C)</span>\ \frac {1}{18} \qquad <span class='latex-bold'>(D)</span>\ \frac {1}{9} \qquad <span class='latex-bold'>(E)</span>\ \frac {9}{80}
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80
1
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B
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40
1
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C
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18
1
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D
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9
1
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E
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80
9
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