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Problems
Contests
National and Regional Contests
Turkey Contests
National Olympiad First Round
2005 National Olympiad First Round
4
4
Part of
2005 National Olympiad First Round
Problems
(1)
P04 [Combinatorics] - Turkish NMO 1st Round - 2005
Source:
11/8/2013
How many
6
6
6
-digit positive integers whose digits are different from
0
0
0
are there such that each number generated by rearranging the digits of the original number is always divisible by
7
7
7
?
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11
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77
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133
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166
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<span class='latex-bold'>(A)</span>\ 11 \qquad<span class='latex-bold'>(B)</span>\ 77 \qquad<span class='latex-bold'>(C)</span>\ 133 \qquad<span class='latex-bold'>(D)</span>\ 166 \qquad<span class='latex-bold'>(E)</span>\ 255
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133
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255