Somebody brought a dead thread back to life... lol
Anyway... I think it depends on what you were taught in school. I was taught that it was 1 simply because in terms of order, multiplication trumps division. But for some, multiplication and division are in the same order and thus you go from left to right, which gives you 9.
So, the fault(s) lies in the school education system and the damn bloody lousy equation that is ambiguous.
Either answer is RIGHT depending on what you are taught.
AND WRONG because what you want is a definitive answer since you can do plenty damage with equations like those. I am a structural engineer. Getting those wrong can cause a building to collapse. Put in the parentheses and remove the ambiguity. That's the CORRECT answer.