Khan/khan-exercises — Issue #12260: Standard deviation - This Whole Practice Set is Flawed
Author: KhanBugz
Created: 2012-01-27 04:21:27+00:00
State: open
Labels: leopard, safari, wrong-or-unclear

Reporter: jake.c.dailey@gmail.com

Variance is incorrectly calculated.

[standard_deviation.html?seed=18&problem=population](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/standard_deviation.html?seed=18&problem=population&debug)

[Answer timeline](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/standard_deviation.html?seed=18&problem=population&debug&activity=%5B%5B%22incorrect-activity%22%2C%22%5B%5C%2213%5C%22%2C%5C%223.1%5C%22%5D%22%2C33%5D%2C%5B%22hint-activity%22%2C%220%22%2C2%5D%2C%5B%22hint-activity%22%2C%220%22%2C2%5D%2C%5B%22hint-activity%22%2C%220%22%2C2%5D%2C%5B%22hint-activity%22%2C%220%22%2C3%5D%2C%5B%22hint-activity%22%2C%220%22%2C3%5D%2C%5B%22hint-activity%22%2C%220%22%2C4%5D%2C%5B%22hint-activity%22%2C%220%22%2C4%5D%2C%5B%22hint-activity%22%2C%220%22%2C8%5D%2C%5B%22hint-activity%22%2C%220%22%2C8%5D%5D)

[["13","3.1"]]

Mozilla/5.0 (Macintosh; Intel Mac OS X 10_5_8) AppleWebKit/534.50.2 (KHTML, like Gecko) Version/5.0.6 Safari/533.22.3

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