5. (5 points) If 6 is placed at the right end of a two-digit number, the resulting three-digit number is 474 greater than the original two-digit number. The original two-digit number is $\qquad$ .
【Solution】Solution: Let the two-digit number be $x$, and the three-digit number be $10 x+6$, $10 x+6-x=474$
$$
x=52
$$

Answer: The original two-digit number is 52.
Therefore, the answer is: 52.