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by sud21 » Thu Jan 12, 2012 9:46 am
Is the standard deviation of a set 0?
1). The average is equal to the greatest number.
2). The median is equal to the average number.

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by user123321 » Thu Jan 12, 2012 10:50 am
sud21 wrote:Is the standard deviation of a set 0?
1). The average is equal to the greatest number.
2). The median is equal to the average number.
1) average equals greatest number => all numbers are same.
so SD = 0. hence suff.

2) median = avg. lets take simple example 1,2,3.
here SD != 0
and if numbers are 1,1,1 then SD = 0
hence insuff.

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