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jerrymacgp | 1 years ago (raw) | root | parent | reply | flag 
 @b541bfe5 1) Everything in parentheses is calculated first: 1 + 2 = 3, reducing the expression to 6 divided by 2 times 3.
2) The convention for order if operations is multiplication & division are at equivalent hierarchical levels & so are calculated in order left-to-right, so 6 divided by 2 = 3.
3) A number preceding parentheses without an operation symbol is multiplication. So then it’s just 3 x 3 = 9.
The correct answer is 9. QED.
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Ned Yeung | 1 years ago (raw) | root | parent | reply | flag 
 @24c03924 Yes, correct. Now it would only be read that way, but way back a lot of us would have assumed the ÷ symbol was just shorthand for writing a problem using / like this:
6
--
2(1+2)

That shorthand was common in my day and printed in exercises, creating an unnecessary ambiguity. So it's not about PEDMAS or lack of understanding the order of operations. The ambiguity came from how mathematical expressions were written in print. We would change it into a fraction when writing "long-form".
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Ned Yeung | 1 years ago (raw) | root | parent | reply | flag 
 @24c03924 In no way is 1 the correct answer, but it must be understood that it could be read as 1 based on misconceptions which were included in school curriculum. That's what makes this an interesting topic.