All natural numbers from 1 to 1000 inclusive are divided into two groups: even and odd.
In which of the groups is the sum of all digits used to write the numbers greater, and by how much?

#
The sum of the digits of the number 1 is equal to the sum of the digits of the number 1000; the remaining numbers will be divided into 499 pairs: $\{2,3\},\{4,5\}, \ldots$, $\{998,999\}$. In each pair, the sum of the digits of the odd number is 1 greater than the sum of the digits of the even number.

## Answer

The sum of the digits of the odd numbers is greater by 499.