Someone told me that the answer to 100 - 26 ÷ 2 + 8 was 95 (not 79 which is what I thought it was). Could they be right?
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2You've evaluated $100-(26/2+8)$. – Michael Hoppe Nov 14 '16 at 22:14
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2Presumably by subtracting the eight as well. I assume that he went by saying $100-26\div 2 + 8 = 100-13+8$ From here, applying addition before subtraction would yield $100-(13+8)=100-21=79$. What is often overlooked when talking about addition and subtraction is that they are of the same importance and should be carried out left-to-right. $a-b+c = a+(-b)+c$ not $a-(b+c)$ – JMoravitz Nov 14 '16 at 22:17
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They are right. By order of operations, the first operation you perform is division, so you divide $26\div 2=13$. You then add and subtract $$100-13+8$$ from left to right: $100-13=87$ and $87+8=95$.
Note that the acronym BODMAS is misleading, because it suggests you do addition before subtraction (and division before multiplication). This is not true. Rather, you perform addition and subtraction at the same time, going from left to right as I did here (and similarly you perform multiplication and division at the same time).
Eric Wofsey
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Do you not use the BODMAS rule after you divide? I thought it would be 26 ÷ 2 to get you 100 - 13 + 8. Do you not then do 13 + 8 because that comes before subtraction? – Richard Sewell Nov 14 '16 at 22:15
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See the latest update to my answer--I figured out how you got $79$ and added something to address that as you were commenting :). – Eric Wofsey Nov 14 '16 at 22:17
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Alternatively, simply write all in terms of addition (after the division): $$100 +-13 + 8$$ Then you can add in whatever order you please. – amWhy Nov 14 '16 at 22:19
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The answer is even 99.333... By applying Bodmas, you consider first the division. so -26/3=-8.666..., then you add 8 to it and 100. Hence, the final answer should be 99.333...
ok, the question is 110-26/2+8. The answer then is 95. -26/2=13, 100-13+8= 95
MogulD
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