## 20 April 2018

### 1089

Choose a three-digit number so that the first and third digits differ two or more units:
1. Write the number from right to left;
2. Do the subtraction of the larger number by the smaller;
3. Write the number obtained in point 2 from right to left and add it to the number also obtained in point 2.
And the result is $1089$.

Example: Consider the number $503$.
1. $305$
2. $503-305=198$
3. $198+981=1089$