the general rule is: adding a to the numerator and b to the denominator moves the resultant fraction closer to the fraction a/b. If x/y < a/b, moving the starting fraction close to a/b will make it bigger. If x/y > a/b, moving the starting fraction close to a/b will make it smaller.
What is the reason behind this general rule ?
![Pray :pray:](./images/smilies/pray.png)