To calculate the variance follow these steps: Work out the Mean (the simple average of the numbers) Then for each number: subtract the Mean and square the result (the squared difference). Then work out the average of those squared differences. Then the standard deviation of X is the quantity. (derived using the properties of expected value). In other words, the standard deviation σ (sigma) is the square root of the variance of X; i.e., it is the square root of the average value of (X − μ)2.
maybe it helped people with health and skin care so maybe it inspired them to also use it for hair and it worked I hope this is something that atleast helped you sorry if it seems stu-pid