Question

How many three digits numbers less than $1000$ can be formed using the digits $1,2,3,4,5,6$ when the digits are not repeated?

Answer 1

$\overline{4}\overline{5}\overline{6}$

Unit's place - 6 ways.

Ten's place -5 ways.

Hundredth's place - 4 ways.

Total no. of digital possible $=6\times 5\times 4$

$=120$