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2022 AMC 10A Question 22

AMC10 · 2022 AMC 10A

Question 22

Suppose that $13$ cards numbered $1,$ $2,$ $3,$ $\cdots,$ $13$ are arranged in a row. The task is to pick them up in numerically increasing order, working repeatedly from left to right. In the example below, cards $1,$ $2,$ $3$ are picked up on the first pass, $4$ and $5$ on the second pass, $6$ on the third pass, $7,$ $8,$ $9,$ $10$ on the fourth pass, and $11,$ $12,$ $13$ on the fifth pass. For how many of the $13!$ possible orderings of the cards will the $13$ cards be picked up in exactly two passes?

Question illustration
  1. $4082$
  2. $4095$
  3. $4096$
  4. $8178$
  5. $8191$