How to find the percentage of something?

This question is similar to the above, but most of the people who ask this specific question are actually referring to the question: Number A is C% of any number. Let's call B for this number to solve this. The first percentage C is expressed as a decimal number divided by 100 and divided by A. B = A / (C / 100). The following example illustrates this more clearly:

Example: 5 is 20% of which number? This number is calculated as 5 / (20/100) = 5 / 0.2 = 25.