2026 AMC 8 Problem 17

Attempt Problem 17 of the 2026 AMC 8 below, then check your answer against the video solution and professionally curated solution from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 2026 AMC 8 solutions, or check the answer key.

All problems are used with official legal permission of the Mathematical Association of America (MAA).

17.

Four students are seated in a row. They chat with the people sitting next to them, then rearrange themselves so that they are no longer seated next to any of the same people. How many rearrangements are possible?
22
44
99
1212
2424
Answer: A
Concepts:arrangements with restrictionspermutations
Small hint:
Name the original order A,B,C,DA,B,C,D
Big hint:
The allowed neighboring pairs are ACAC, ADAD, and BDBD
Video solution:
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Written solution:
Name the original order A,B,C,DA,B,C,D. The forbidden neighboring pairs are ABAB, BCBC, and CDCD, so the only allowed pairs are ACAC, ADAD, and BDBD. To seat all four students in a row, the three row-adjacencies must be exactly these three edges, giving C,A,D,BC,A,D,B or its reverse. There are 22 rearrangements.
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