Despite constantly bragging about his cognitive test scores, Donald Trump appears to struggle with the concept of percentages.

"Trump creates and inhabits his own reality with his own rules," Seth Meyers explains in the Late Night monologue above. "He even has his own math. In our world, you can only reduce the price of something by 100 percent max. Once you've reduced it 100 percent it's free. But in Trump's world, numbers work very differently."

Cue a montage of Trump saying he wants to reduce various things by various percentages well over 100, ending with the president explaining that with numbers, "It's all about the phrasing of the question."

"No!" says Meyers. "It's not! Math is math. There's no math problem where the answer is '500 or 600 or 80 or 75.' I don't remember that from my AP algebra days."

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