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National and Regional Contests
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MAA AMC
AMC 8
2011 AMC 8
22
Tens Digit
Tens Digit
Source:
November 23, 2011
algebra
binomial theorem
Problem Statement
What is the tens digit of
7
2011
7^{2011}
7
2011
?
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A
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0
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B
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1
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C
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3
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D
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4
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E
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7
<span class='latex-bold'>(A)</span>0\qquad<span class='latex-bold'>(B)</span>1\qquad<span class='latex-bold'>(C)</span>3\qquad<span class='latex-bold'>(D)</span>4\qquad<span class='latex-bold'>(E)</span>7
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0
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1
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C
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3
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D
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4
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E
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7
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