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Problems
Contests
National and Regional Contests
USA Contests
MAA AMC
AMC 8
2011 AMC 8
22
22
Part of
2011 AMC 8
Problems
(1)
Tens Digit
Source:
11/23/2011
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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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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1
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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
algebra
binomial theorem