Hi, I wasn't sure how to approach this problem:(adsbygoogle = window.adsbygoogle || []).push({});

You have 5 differently colored stones-red, orange, blue, green, purple. If the green stone cannot be placed at the front or the back of the sequence, how many possible arrangements can you make?

I know that without the above restriction, the amount would be 5!=120.

But I don't get how to use the restriction.

BTW the back of the book says that the answer is 72.

Help please! thanks.

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# Homework Help: Counting Problem

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