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VCE Stuff => VCE Mathematics => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE General & Further Mathematics => Topic started by: nooshnoosh95 on November 01, 2012, 06:13:07 pm

Title: question3 vcaa 2010
Post by: nooshnoosh95 on November 01, 2012, 06:13:07 pm
on exam 1 i dont get how they got 2 degrees as the standard deviation
i did the range (approx 186-173) over 6 only because that seemed logical but is there an actual rule?
Title: Re: question3 vcaa 2010
Post by: dfgjgddjidfg on November 01, 2012, 06:16:53 pm
that is basically the rule for normal distributions. Range/6. but you could also start at the mean(same as median for symmetrical distributions) and move 34% to the left or right of the mean which is equal to 1 SD away from the mean
Title: Re: question3 vcaa 2010
Post by: Stick on November 01, 2012, 06:18:58 pm
Yeah, what you did is the logical rule: range/6. When the data is symmetrical, you use this formula. However, use range/4 if the shape of the data is skewed or unknown. :)
Title: Re: question3 vcaa 2010
Post by: nooshnoosh95 on November 01, 2012, 06:20:24 pm
okay cool
thanks guys! :)