The number of 3 digit odd numbers, that can be formed by using the digits 1,2,3,4,5,6 when the repetition is allowed is

Extreme left place can be filled in 6 ways. The middle place can be filled in 6 ways and extreme right place in only 3 ways                (∵  number to be formed is odd)∴  Required number of numbers              =6×6×3=  108