The total number of permutations of n ( > 1 ) different things taken not more than r at a time, when…
The total number of permutations of different things taken not more than at a time, when each thing may be repeated any number of times is
None of these
Solution
When we arrange one things at a time, the number of possible permutations is When we arrange them two at a time the number of possible permutations are
and so on. Thus, the total number of permutations are