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There are 2! = 2 permutations inside the block of 2 Physics books;
4! = 24 permutations inside the block of 2 Math books; and
3! = 6 permutations inside the block of 3 Chemistry books.
Also, there are 3! = 6 permutations of these 3 blocks as whole items.
THEREFORE, the are 2*24*6*6 = 1728 different permutations under the posed conditions, in all.
Solved, answered, explained and completed.
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On permutations, see the lessons
- Introduction to Permutations
- PROOF of the formula on the number of Permutations
- Simple and simplest problems on permutations
- Special type permutations problems
- Problems on Permutations with restrictions
- Fundamental counting principle problems
in this site.
Also, you have this free of charge online textbook in ALGEBRA-II in this site
- ALGEBRA-II - YOUR ONLINE TEXTBOOK.
The referred lessons are the part of this online textbook under the topic "Combinatorics: Combinations and permutations".
Save the link to this textbook together with its description
Free of charge online textbook in ALGEBRA-II
https://www.algebra.com/algebra/homework/complex/ALGEBRA-II-YOUR-ONLINE-TEXTBOOK.lesson
into your archive and use when it is needed.
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Do not forget to post your "THANKS" for my teaching.