5. In the equation below, four small pieces of paper each cover a digit. What is the sum of the four digits that are covered?



The text above is the translation of the provided Chinese text, maintaining the original format and line breaks.
5.【Solution】The unit digit of 149 is 9, which indicates that the sum of the two unit digits did not carry over, so 9 is the sum of the two unit digits, and 14 is the sum of the two tens digits. Therefore, the total sum of the four digits is $14+9=23$.