Grouping can sound vague to me, is six divided by 2 "grouped"? Quin's BODMAS is the most accurate, but it really doesn't matter what you use. I hate seeing "PEMDAS" vs. x arguments because none of this matters if...
A. If you speak English, treat the math like English and read left to smurfing right when using your favorite acronym. Whoever made that calculator that got the answer of one is a smurf and as a computer engineer I am appalled. English mothersmurfer do you speak it???
B. Understand the math that is going on, don't use the division sign, use fractions because it makes it abundantly clear what's going on. When that isn't an option (aka you are putting your fraction math into your calculator for a numerical answer) put parenthesis smurfing EVERYWHERE. A calculator is only as smart as whoever programmed it (unless its a TI-84, in which case it can probably do more math than you will ever understand).
And if you ever get any other weird results from your calculator...
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