How many three digit odd nos. can be formed from the digits : 2, 0, 3, 5?(repetition not allowed)
Simple way to solve the issue would be the place that is more restricted should be filled first.
Unit digit place can be filled in two ways (by 3 or 5 only) while the
hundred's place can be filled in three ways (by 2 or 3 or 5).
Therefore starting from the unit's place we can form the nos. in 2 x 2 x 2