Question

The greatest $4$ digit number with $3$ different digits is _____ .

Answer 1

Write the greatest $4$ digit number with $3$ different digits.

We know that we have in total $10$ digits, those are $0,1,2,3,4,5,6,7,8,9$. So among them we have to take $3$ different larger digits, so we can take take$9,8$ and $7$.

As we have to write the greatest number so we will place digits from left to right in decreasing manner and we will choose the fourth number $9$ as it is the greatest among the taken numbers.
Write $9$in thousands position, $9$ in hundreds position, $8$ in tens position and $7$in the last place that is one's position.
So the required number is $9987$.

Hence, the greatest $4$ digit number with $3$ different digits is $\underline{9987}$ .