How many words can be formed with or without meaning by using three letters out of k, l, m, n, o without repetition of alphabets.

Given letters are k, l, m, n, o = 5

number of letters to be in the words = 3

Total number of words that can be formed from these 5 letters taken 3 at a time without repetation of letters =  $5P3 \mathrm{ways}.$

$\Rightarrow 5P3 = 5 x 4 x 3 = 60 \mathrm{words}.$