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National and Regional Contests
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MAA AMC
AMC 10
2004 AMC 10
2
Two-Digit Numbers with a 7
Two-Digit Numbers with a 7
Source:
January 15, 2009
Problem Statement
How many two-digit positive integers have at least one
7
7
7
as a digit?
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A
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10
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B
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18
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C
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19
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D
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20
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E
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30
<span class='latex-bold'>(A)</span>\ 10\qquad <span class='latex-bold'>(B)</span>\ 18\qquad <span class='latex-bold'>(C)</span>\ 19\qquad <span class='latex-bold'>(D)</span>\ 20\qquad <span class='latex-bold'>(E)</span>\ 30
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10
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B
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18
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C
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19
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D
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20
<
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(
E
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30
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