How to make a automated If in between statement using percentages in php

I have a statement that works but it works with minimum and maximal variables that I get from a database. The thing im struggeling with is a percentage variant, I count the amount of $res ( response) in the database and with that number I make a percentage. So I know what the percentage is but not hoe to use it in a statement like this.

It has to be automated.

I hope anyone can help me with this.

if ($Score >= $min && $Score<= $max) {
       echo $res;
    }