Question

How many $3$digit numbers by using the digits $0,1,3,4,6,7$can be possible if repetition is allowed?

Answer 1

To find the total numbers:

Repetition is allowed and digits $0,1,3,4,6,7$

Ways to fill the first digit of the number $=5$ (Since $0$ cannot be in the first place)

Ways to fill the second digit of the number$=6$

Ways to fill the third digit of the number $=6$

Thus total $3$digit numbers $=5\times 6\times 6=180$

Hence, the total number of $3$digit numbers that can be formed is$180$