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2017 AIME I Question 11

AIME · 2017 AIME I

Question 11

Consider arrangements of the $9$ numbers $1,$ $2,$ $3,$ $\ldots,$ $9$ in a $3 \times 3$ array. For each such arrangement, let $a_1,$ $a_2,$ and $a_3$ be the medians of the numbers in rows $1,$ $2,$ and $3,$ respectively, and then let $m$ be the median of $\{a_1, a_2, a_3\}.$ Let $Q$ be the number of arrangements for which $m = 5.$ Find the remainder when $Q$ is divided by $1000.$