Khan/khan-exercises — Issue #12371: Standard deviation - standard deviation
Author: KhanBugz
Created: 2012-01-29 03:53:12+00:00
State: open
Labels: firefox, other, vista

When using a TI-84 to calculate the standard deviation with the one variable stats, sometimes the accepted answer is Sx and sometimes the accepted answer is ox. Why isn't it consistent?

[standard_deviation.html?seed=29&problem=population](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/standard_deviation.html?seed=29&problem=population&debug)

[Answer timeline](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/standard_deviation.html?seed=29&problem=population&debug&activity=%5B%5B%22incorrect-activity%22%2C%22%5B%5C%2213%5C%22%2C%5C%223.1%5C%22%5D%22%2C21%5D%2C%5B%22correct-activity%22%2C%22%5B%5C%2213%5C%22%2C%5C%222.8%5C%22%5D%22%2C3%5D%5D)

[["13","3.1"],["13","2.8"]]

Mozilla/5.0 (Windows NT 6.0; WOW64; rv:9.0.1) Gecko/20100101 Firefox/9.0.1

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