Question

When this 3-digit number is rounded to the nearest ten or hundred, the numbers round up.  All of the digits in this number are the same.  The sum of the digits is 15. what is the number

Answer 1

I don't need to know anything about all that rounding stuff.

You said that there are 3 digits, they are all the same, and their sum is 15.

So each of them must be  ( 15 / 3 )  =  5 .

The number is  555 .