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 Question from Robert: To whom it may concern, I am having some difficulty with the following equation: 200 * 5 / 2 - 450 + 25 When I work out the equation, I end up getting an answer of 25. This occurs because I am Canadian, thus I always apply the rules of the order of operations known as BEDMAS (Brackets, first; Exponents, second; Division, third; Multiplication, fourth; Addition, fifth; and Subtraction, sixth) and not America's PEMDAS, where multiplication and division are calculated according to which one is furthest to the left, and the same goes for addition and subtraction when dealing with their order. Here is how I would answer this equation: 200 * 5 / 2 - 450 + 25 = 200 * 2.5 - 450 + 25 = 500 - 450 + 25 = 500 - 475 = 25 However, I am reminded that you may have to pay attention to integers in this equation, particularly during the last few parts of this equation. This is especially true seeing that 450 is actually -450. So when adding -450 + 25, the outcome is -425, thus yielding an answer of 75. Therefore, the second half of the same equation could look like this: = 500 - 450 + 25 = 500 - 425 = 75 Therefore, I would greatly appreciate it if someone could answer this equation step-by-step just to see which way is the right way to answer this troubling equation.

Robert,

500 - 450 + 25 should be read from left to right as: start with 500, subtract 450, then add 25. You have interpreted it as: start with 500 and then subtract (450 + 25). But 450 + 25 isn't bracketed.

BEDMAS

• do what is in t he Brackets first

• do Exponents next

• Multiply and Divide (left to right, no precedence) before you

• Add and Subtract (left to right, no precedence).

Victoria

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