PEMDAS stands for Parentheses, Exponents, Multiply, Divide, Add, and Subtract.
How to use it?
Well, if you have a problem like:
19 + 4 x 3.
If someone didn't know the rule of PEMDAS, they would start from the beginning of the problem, but no.
If you follow the rule, MULTIPLYING comes before ADDING. So you need to solve whatever comes first in PEMDAS.
4 x 3 = 12, then plus 19 = 31
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