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What is 48÷2(9+3)?
Please, look at the picture?
Which calculator shows true result and how to prove achieved result?
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1correct answer is 9 – Aang Jun 28 '12 at 12:26
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@avatar why you think so? can you proove your suggestion? – Tural Ali Jun 28 '12 at 12:28
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@BenjaLim: Apparently there was a period some time (more than a year) ago when the site was overwhelmed with variants of this question. Seeing it again must have been a traumatic experience for someone. – hmakholm left over Monica Jun 28 '12 at 12:48
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2The Casio fx-570MS to the left is a model from 2005, whereas Casio fx-50FH was introduced in 2008, so I would go with the newer calculator on the right. Which, incidentally, has the right answer. – Per Erik Manne Jun 28 '12 at 13:08
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I have given an answer here which explains why calculators give different results. The question to which it has been originally linked to is somewhat too broad. https://math.stackexchange.com/a/2356210/54967 – noir1993 Jul 12 '17 at 14:20
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One of the calculators may be a regular one and the other may be a scientific one. Unlike regular four-function calculators, scientific calculators follow order of operations. – Marvin May 10 '19 at 19:45
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Despite every personal belief, a notation like $a/b(c+d)$ is ambiguous. At school I learned that this should be $$ \frac{a}{b}(c+d), $$ but even in research papers somebody could read $$ \frac{a}{b(c+d)}. $$
Siminore
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The reason why calculators are giving different results is because one is calculating,
$$\frac{6}{2\cdot(2+1)} = 1$$
while the other is calculating,
$$\frac{6}{2}\cdot(2+1) = 9$$
Depending on what you want to calculate, you could obtain different answers.
Guy
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Jorge Leitao
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when two operations have same precedence, then the operations are done from left to right.So here, division is done first and then multiplication.This is just a convention.Without this, this expression is ambiguous.
Aang
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