How many permutations of the letters a, b, c, d, e, f, g have either two or three letters between a and b?(adsbygoogle = window.adsbygoogle || []).push({});

My guess for this is that if a and b have to have two letters between them, then there are 5! ways to arrange the rest of the letters, right? Same deal if a and b have to have three letters between them. So:

5! + 5!

Would be my answer. Am I anywhere close with this one? Thank you.

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# Permutations of the letters a, b, c, d, e, f, g

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