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Comment by baddox | Hacker News Reader

Obviously, the author is right that there is no universal objective definition of the order of operations. Still, I find it surprising that anyone with a high school level mathematics education would perform the division via the obelus (÷) before the multiplication via juxtaposition.

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In high school (and college) I've always been taught that multiplication and division have equal precedence and should be evaluated in the order in which they are encountered.

Was multiplication by juxtaposition ever mentioned explicitly? I was taught to give them equal precedence, but that was explicitly for the division symbol and the multiplication symbol (* or x). Juxtaposition, like 2x or 2(2+1), was always considered to have greater precedence than the division and multiplication symbols.

Nope, never heard that in my 13 years of school in Germany.

Psst... the programmers at google might have a bone to pick with you.

I strongly suspect that to be an oversight.

also note that the author skips the multiplication operator. Especially odd (to me) since he is using parenthesis to imply multiplication and the values are not variables but values.

If the expression were 6÷2x(1+2)=?, then my intuition would be to evaluate from left to right (division before multiplication). But removing the x symbol makes me want to perform the multiplication via juxtaposition first, just like if it were 6÷2x. Would anyone really interpret 6÷2x as 3x?

note: I had to use an x instead of the asterisk to represent multiplication, since I don't know how to escape the asterisk in Markdown.

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