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1985 AMC 12 Question 9

AMC12 · 1985 AMC 12

Question 9

The odd positive integers, $1,$ $3,$ $5,$ $7,$ $\ldots,$ are arranged in five columns continuing with the pattern shown. Counting from the left, the column in which $1985$ appears is the $$
\begin{array}{ccccc} &1&3&5&7\\ 15&13&11&9&\\ &17&19&21&23\\ 31&29&27&25&\\ &33&35&37&39\\ 47&45&43&41&\\ &49&51&53&55 \end{array}
$$
  1. first
  2. second
  3. third
  4. fourth
  5. fifth