When I was in school, we were taught the expression “Please Excuse My Dear Aunt Sally” to help us remember what the order of operations was when we had a math problem in front of us with a bunch of different steps to it.
It always amazes me how stuff that I learned in 5th or 6th grade, if not earlier, still comes to mind when I look at something I would have done back then. As I mentioned in the caption for the above image, the problem on the right is wrong. You’re supposed to do addition before subtraction, so it should read 10 – 17, not 1 + 8. The answer should be -7, but hey. Maybe I’m the dumb one.