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Question on II-A Combinatorics

Picture of Bober Yang
Question on II-A Combinatorics
by Bober Yang - Monday, March 1, 2021, 8:42 PM

Hi, I have a question on II-A Chapter 2 Combinatorics. Question number 2.28, in the answer key it said 6!*5!*7*6. I am kind of confused about the ordering of the German books. In the problem, am I suppose to first order the German books which is 6!. Then I have 7 spaces left for Spanish or France. In conclusion, I think it would be  6!*7*6*6!*5! because imagine the books in a bag and you have 7 places to put it and then the second bag only has 6 places left. Then in each bag, you can reorder the books. It would be great if someone can help me with this question.

Thank you so much!

Best Bober

Picture of John Lensmire
Re: Question on II-A Combinatorics
by John Lensmire - Friday, March 5, 2021, 11:36 AM

Thanks for letting us know.

6!*7*6*6!*5! is correct. I'm guessing you saw the answer in the print book? It's possible that there was a typo there. Remember you can always review the question (plus the solution) by looking at the MC II-A homework.

You can also find answer keys online here: