Statistics · built from real SSC papers

Mean, Median & Mode

Turn “total = mean × count” into a reflex, sort before you take a median, and use one-line formulas for grouped data, the empirical relation and dispersion. Pick any topic — nothing is locked.

6 topics · every exam question type

➕1. Mean (Average)Sum ÷ count, missing values, weighted mean2 types 📏2. MedianMiddle of sorted data; grouped-data formula2 types 🔢3. ModeMost frequent value; modal-class formula2 types 📋4. Mean of Grouped DataAssumed-mean & step-deviation shortcuts1 type ⚖️5. Empirical Relation & EffectsMode = 3 Median − 2 Mean; add / remove / shift4 types 📊6. Variance & Standard DeviationSpread of data, SD = √variance, scaling1 type