text: what is a population variance? in math? i have a problem with stats. it gives me like a few numbers : 75,80,85,95,90...i don't know what a pop var is though...booo help anyone????????? for finding out the population variance in general:  1. find the arithmetic mean of the population concerned.  2. for each member of the population,  find the value of its deviation from the arithmetic mean, and square it(by deviation i mean difference) .  3. add all the squares so obtained, and divide them by the population size.   the number that you would now obtain is the variance of the population. hope this helps.