let' look at what happens thereso (- ) is positive and (- ) ends up being much smaller numberthat is because that' much closer to the mean of also ( ) turned out to be close to the meanonly but as we get up to the positive outlier( ends up being that gives us( to find the actual variance valuewe just take the average of all those squared differences so we add up all these squared variancesdivide the sum by that is number of values that we haveand we end up with variance of okthat' all variance is standard deviation now typicallywe talk about standard deviation more than varianceand it turns out standard deviation is just the square root of the variance it' just that simple soif had this variance of the standard deviation is so you see now why we said that the variance ( ) it' because itself represents the standard deviation soif take the square root of ( ) get sigma that ends up in this example to be