1. (7 points) In a three-digit number, the first digit (hundreds place) was increased by 3, the second digit by 2, and the third digit by 1. As a result, the number increased by 4 times. Provide an example of such an original number.

Answer: 107.
Solution. The answer can be found in the following way. Let $x$ be the desired number. Then the condition of the problem immediately leads to the equation $x+321=4x$, the only solution of which is $x=107$.

Criteria. Correct answer, even without any comments: 7 points.

Incorrect answer: 0 points.