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DS...SD...

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DS...SD...

by ontopofit » Thu Feb 19, 2009 12:47 pm
What is the standard deviation (SD) of the four numbers p, q, r, s?
1. The sum of p, q, r and s is 24
2. The sum of the squares of p, q, r and s is 224
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Re: DS...SD...

by x2suresh » Thu Feb 19, 2009 2:33 pm
ontopofit wrote:What is the standard deviation (SD) of the four numbers p, q, r, s?
1. The sum of p, q, r and s is 24
2. The sum of the squares of p, q, r and s is 224
C .


VARIANCE =SD^2 = 1/N { SUM (Squares of numbers) - Avg(numbers)^2 }
= 1/4*(224 - 36)
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