re: Spinoff: X=6/2(2+1)

You read it that way because you are reading it left to right. Rules that govern reading a sentence do not govern math equations. You are right that people who answer 1 choose to do the order of operations as if the parenthesis were put that way. But those answering 9 are doing the same thing. You can't assume people will do operations left to right, because that's not a rule.

As someone else said, its up for interpretation until its written correctly.