This thread is hurting my brain. Math actually does have universal rules and the order of operations is one of them. If you solve the problem as written following the order of operations correctly, the answer is 7. It's not open to interpretation. I don't think people are stupid or uneducated for getting it wrong; it's more than understandable not to remember math you learned as a kid (and likely haven't used or thought about for many years) with perfect accuracy. I've forgotten probably 90% of what I learned in school (sigh). That's why shows like "Are You Smarter Than a 5th Grader" are fun - we know adults aren't stupid for not knowing the answers to elementary level questions.

I really doubt anyone was taught to solve math problems from left to right regardless of PEMDAS. I think people are misremembering and were actually taught to solve left to right when the order of operations does not apply, for example x+y+z. Again, that doesn't make anyone less intelligent, but it also doesn't make them less incorrect, and it doesn't mean that math rules are ambiguous.