A relay team with a feud

MediumCombinatorics~4m

From 8 runners, an ordered relay team of 4 is chosen (each of the 4 legs is a distinct runner and the running order matters). Two of the runners, Ann and Ben, are feuding and refuse to be on the team together. How many ordered teams are possible?

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Complement: all ordered teams $P(8,4)$ minus those containing both feuding runners.
Teams with both = (place the pair into 2 of 4 ordered legs) $\times$ (fill the rest): $P(4,2)\cdot P(6,2)$ .

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A relay team with a feud

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