What is the definition of Payday Math?

"Payday math" is the fancy name for that ridiculous math problem you get when you're trying to figure out how much you owe a cashier for a late payment on your rent, plus the interest that's been building up like a wildfire. It's the kind of math where even your calculator starts giving you a "calculator's conscience" and you're left scratching your head, wondering if you should've opened a savings account while you were at it.

---

Here's an unsettling example sentence using this term: "I had to resort to payday math after my landlord decided to charge me interest on the $100 late fee for not paying rent on time, making my monthly mortgage payments sound like a game of 'Monopoly' with my credit score."