Question:medium
If $^{5}P_r = {}^{6}P_{r-1}$, then the value of $r$ is
If $^{5}P_r = {}^{6}P_{r-1}$, then the value of $r$ is
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In permutation equations, always reduce factorial expressions step-by-step and cancel common terms early to simplify quickly.
Updated On: Apr 30, 2026
- $r = 1$
- $r = 5$
- $r = 3$
- $r = 2$
- $r = 4$
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The Correct Option is D
Solution and Explanation
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