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Problems
Contests
National and Regional Contests
USA Contests
MAA AMC
AMC 8
2009 AMC 8
5
5
Part of
2009 AMC 8
Problems
(1)
Sequence of Numbers
Source:
11/26/2009
A sequence of numbers starts with
1
1
1
,
2
2
2
, and
3
3
3
. The fourth number of the sequence is the sum of the previous three numbers in the sequence: 1\plus{}2\plus{}3\equal{}6. In the same way, every number after the fourth is the sum of the previous three numbers. What is the eighth number in the sequence?
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A
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11
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20
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C
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37
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D
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68
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E
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99
<span class='latex-bold'>(A)</span>\ 11 \qquad <span class='latex-bold'>(B)</span>\ 20 \qquad <span class='latex-bold'>(C)</span>\ 37 \qquad <span class='latex-bold'>(D)</span>\ 68 \qquad <span class='latex-bold'>(E)</span>\ 99
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11
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20
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37
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D
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68
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E
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99