the standard deviation of 5, 5, 5, 2, 5, 3, 5 is not 924.4, and the mean is not 12

I've been playing with this elderly Radio Shack scientific calculator I have, and when it took me five tries to get a correct set of standard deviation answers, I figured out that its code has undocumented gotchas like "clearing the calculator in standard deviation mode doesn't actually clear out everything, some of the registers still have crap in them and you have to clear it repeatedly in multiple modes or your answers will be strange after the first time you use it, and this persists even if you power it off in between runs, and by the way, we don't tell you this anywhere." Since WarGames taught us all that the only way to win that kind of game is not to play, I need a new calculator.

[Poll #754638]