Problem 3. The sum of two numbers is 836. The digit in the units place of one of the numbers is 0. If the digit in the units place of this number is removed, i.e., the digit 0 is removed, the second number is obtained. What are these numbers?
Solution. From the condition of the problem, it follows that the required numbers are $\overline{x y 0}$ and $\overline{x y}$. Now, from $\overline{x y 0}+\overline{x y}=836$, we conclude that $y=6$, i.e., the numbers are $\overline{x 60}$ and $\overline{x 6}$. Further, from $\overline{x 60}+\overline{x 6}=836$ it follows that $x=7$. Therefore, the numbers are 760 and 76.