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Find R If 5p_R = 2^6 P_(R-1) Permutations, - Mathematics

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Question

Find r if `""^5P_r = 2^6 P_(r-1)`

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Solution

∴0 ≤ ≤ 5

Hence, r ≠ 10

r = 3

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Chapter 7: Permutations and Combinations - Exercise 7.3 [Page 148]

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NCERT Mathematics [English] Class 11
Chapter 7 Permutations and Combinations
Exercise 7.3 | Q 7.1 | Page 148

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