a population has SS =100 and variance = 4. how many scores in population

Assuming SS is sum of squares then you can write:

 

V = (SS -n*m^2)/n     where V is variance, SS is sum of squares, n is number in population and m is mean.

 

You can rearrange this to get n in terms of the other parameters, but you'll need to know the value of m to get a numerical value for n.

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