List them in a column, like this 60 49 58 45 55 62 49 Subtract the mean, 54, from each one in the next column, like this 60 60 - 54 = 6 49 49 - 54 = -5 58 58 - 54 = 4 45 45 - 54 = -9 55 55 - 54 = 1 62 62 - 54 = 8 49 49 - 54 = -5 Square these results in the next column 60 60 - 54 = 6 (6)2 = 36 49 49 - 54 = -5 (-5)2 = 25 58 58 - 54 = 4 (4)2 = 16 45 45 - 54 = -9 (-9)2 = 81 55 55 - 54 = 1 (1)2 = 1 62 62 - 54 = 8 (8)2 = 64 49 49 - 54 = -5 (-5)2 = 25 Add those squares up, like this 60 60 - 54 = 6 (6)2 = 36 49 49 - 54 = -5 (-5)2 = 25 58 58 - 54 = 4 (4)2 = 16 45 45 - 54 = -10 (-9)2 = 81 55 55 - 54 = 1 (1)2 = 1 62 62 - 54 = 8 (8)2 = 64 49 49 - 54 = -5 (-5)2 = 25 ----- 248 There are 7 numbers. Subtract 1, getting 6 Divide 248 by 6, getting 41.33333333 Take the square root of 41.33333333, getting 6.429100507 That's the standard deviation Edwin