public static double StandardDeviation(IEnumerable‹double› sequence) { // Step 1: Compute the Mean: var mean = sequence.Average(); // Step 2: Compute the square of the differences between each number // and the mean: var squaredMeanDifferences = from n in sequence select (n - mean) * (n - mean); // Step 3: Find the mean of those squared differences: var meanOfSquaredDifferences = squaredMeanDifferences.Average(); // Step 4: Standard Deviation is the square root of that mean: var standardDeviation = Math.Sqrt(meanOfSquaredDifferences); return standardDeviation; }