Question

how many words with or without dictionary meaning can formef using all the letter of word " mother" using each letter exactly once

Answer 1

$total \: no \: of \: words \: = \binom{6}{6} \times 6factorial \\ = 720$

Answer 2

In the word Mother there are 6 letters.
It is given that the word can be meaningful or meaningless and repetition is not allowed.
Thus,
Total number of words = 6! = 720