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Circular permutations
Maths & Stats
Sir, while solving the question about arranging 7 boys around a circular table such that two particular boys never sit together, you first explained that without any restriction the number of ways is (7-1)! = 6! Then, to find the cases where those two boys always sit together, you said we can consider them as one unit. That makes it 6 places, but you mentioned it as 5 places. I am confused about this step. Could you explain it again? Video Details ------------- Business Mathematics Basic Concepts of Permutations and Combinations #10. Illustrations on Circular & Linear Permutations - Part 1
Answers (1)
Arranging n boys around a circular table is done in (n-1)! ways. For 7 boys its 6! ways When 2 boys are always together then we take these 2 boys as one unit . Now n becomes 6 ( 2 boys as 1 unit + remaining 5 boys) . So total ways is (n-1)! which is 5!. Trust this clarifies
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