Question

How many $3$ letter words with or without meaning can be formed out of the letters of the word $SMOKE$ when repetition of words is allowed?

Answer 1

The number of objects$\left(n\right)$, in this case, is $5$, as the word $SMOKE$ has $5$ alphabets.

and $r=3$, as $3$-letter word has to be chosen.

Thus, the permutation will be:

Permutation (when repetition is allowed)
$=5\times 5\times 5=125$