you need to find the mean on these numbers that is step one in finding standard deviation. so this is 44.2. now you need to subtract the mean from each number and square the result. after that step you now have these numbers.... 3.24, 139.24, .64, .4,.64,282.24,116.64,77.44,27.04. now the next step is to find the mean of these numbers. you get 71.9 appx.. now all you do is square root this number you get 8.5 when you round to the nearest thenth