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Question
The number of permutations of n different objects, taken r at a line, when repetitions are allowed, is ______.
Solution
The number of permutations of n different objects, taken r at a line, when repetitions are allowed, is nr.
Explanation:
Number of permutations of n different things taken r at a time
When reception is allowed = filling r places with the help of n different objects when reception is allowed
= n × b × n ... r times
= nr
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