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| − | ==Problem==
| + | #redirect [[2022 AMC 10A Problems/Problem 22]] |
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| − | Suppose that 13 cards numbered 1, 2, 3, . . . , 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.
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| − | For how many of the 13! possible orderings of the cards will the 13 cards be picked up in exactly
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| − | two passes?
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| − | ==Solution by OmegaLearn Using Combinatorial Identities and Overcounting==
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| − | https://youtu.be/gW8gPEEHSfU
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| − | ~ pi_is_3.14
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| − | ==Solution==
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| − | https://youtu.be/ZGqrs5eg6-s
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| − | ~Steven Chen (Professor Chen Education Palace, www.professorchenedu.com)
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| − | == See Also ==
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| − | {{AMC12 box|year=2022|ab=A|num-b=18|num-a=20}}
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| − | {{AMC12 box|year=2022|ab=A|num-b=21|num-a=23}}
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| − | {{MAA Notice}}
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