What is the logic behind PEMDAS?

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I know some places use BIDMAS as well. Overall though, to someone who knows little about mathematics, why is this the correct order? What’s the exact logic behind it

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Anonymous 0 Comments

First of all, it’s a convention. It’s only correct because people agreed on it. The point is to make sure that whenever people write a mathematical formula, it will always be read the same way. It would work just as well if we used “PASMDE”, we would just have to put some parenthesis differently to get the same expressions.

As to why this specific order was chosen, it simply makes writing certain expressions easier. Parenthesis always come first because that’s their entire purpose – to change the order of operations. The rest are ordered by magnitude – the “strongest” operations first, followed by the “weaker” operations.

This is useful because we like to group expressions by the strongest operations. Specifically, PEMDAS allows us to write polynomials such as 5x^7 + 4x^4 – 2xy^2 – 7y + 5 without any parentheses. A different order of ope

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