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Calculate mean, median, mode, range, count and sum from a pasted data set with visible parsing and formulas.

Calculate exact calendar age in years, months and days plus total days and completed weeks.

Calculate harmonic mean for positive rates and inspect the reciprocal sum used by the formula.

Calculate a frequency-weighted mean from values or class midpoints and show sum of fx and total frequency.

Calculate gestational weeks and days from an LMP or known due date to a selected reference date.

Calculate geometric mean for positive values using a logarithmic method that avoids premature product rounding.

Calculate minimum, Q1, median, Q3, maximum and IQR with the median-of-halves convention stated beside the result.

Calculate a 2x rate and earnings for explicitly qualifying double-time hours without implying legal entitlement.

Generate an audit-ready summary of center, spread and quartiles with visible sample/population and quartile conventions.

Calculate sample or population covariance from paired X and Y lists and inspect the cross-deviation sum.