The act of justifying an otherwise irrational purchase, through application of flawed logic, logical fallacies, and liberal use of arithmetical gymnastics; often with little to no true bearing on the actual costs of the purchase, or value at play.
E.g. "If I buy the Porsche 911 instead of leasing it, it should cost less, as I'm amazing at selling cars, and this one's great and will probably increase in value cos it's black. So that's like, erm, $90,000, less what, $10k for depreciation... so yeah I can afford it, it'll only cost me $10k to run the car... Yeah It's kinda man math but yeah!"
by DrPep July 26, 2019
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The act of loosely guestimating whether a goal is achievable, often without fully thinking through the ramifications of achieving said goal.
Last month, Joe used Man Maths to work out he could just about afford an iPad with his disposable income and purchased one, however a week later he ended up receiving an on-the-spot fine for being stellard in public and this took him into his overdraft.
by FoxdieUK July 6, 2010
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An exxageration to make something look like a success. Something that people do who don't try as hard as the rest of us. Someone said that there were well over a million people at the million man march when they were actually less than 400,000.
A: There is no way that he drank that many beers, he's using his million man math again.

B: Typical for his kind.
by sneekix November 23, 2006
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Bruh mans know math I don need no calculator
Ms. Sanders says you use urs calculator I say nu mans know as maths.
The next day get F on homework.
Mans know math is a saying from Asian Big Shak
by Hdksks February 1, 2018
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