The number of permutations of n objects taken r at a time is:

1. A n! / (n-r)! Correct answer
2. B n! / r!
3. C n! / (r!(n-r)!)
4. D (n+r-1)! / r!(n-1)!

Solution

P(n,r) = n!/(n-r)! — arrangements of r distinct objects from n.

About this question

Subject: Mathematics · Chapter: Permutations and Combinations · Topic: Permutations

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