% is called a modulus. It will not do what you are trying to accomplish.
As a note you can convert any percent into decimal by moving the decimal to the right two places
5% == 0.05 75% == 0.75
Easy, now when you write your code just write your percent as that and multiply or divide as needed.
To get a good tip let's write a function using this knowledge.
def give_good_tip(bill): return bill + (bill * 0.15) print(give_good_tip(25.13))
As you can see it is quite easy to use percentages if you remember this simple trick.