| Value (xi) | Frequency (fi) | Remove |
|---|---|---|
| Lower (L) | Upper (U) | Frequency (f) | Remove |
|---|---|---|---|
Results
Example Data
These examples illustrate formats supported by the calculator.
| Type | Data | Mean |
|---|---|---|
| Raw | 8, 10, 12, 14, 16, 18 | 13 |
| Value‑Frequency | (10,2), (12,3), (15,5), (18,2) | 14 |
| Grouped Intervals | [0–10):4, [10–20):6, [20–30):5 | ≈ 16.8 |
Formulas Used
- Raw (ungrouped) data:
μ = (Σ xi) / n - Discrete distribution:
μ = (Σ xi fi) / Σ fi - Grouped intervals (approximate):
μ ≈ (Σ mi fi) / Σ fi, wheremi = (Li + Ui) / 2
How to Use This Calculator
- Choose an input mode: Raw Data, Value‑Frequency, or Grouped Intervals.
- Enter numbers, pairs, or intervals with frequencies. Use the examples as templates.
- Click Calculate Mean to compute the arithmetic mean and see detailed steps.
- Export the results and inputs using Download CSV or Download PDF.
- Fix any highlighted validation errors and recalculate as needed.
FAQs
Dataset A — Discrete Distribution Example (Value–Frequency)
Small sales basket counts observed over 12 customers.
| xi (items) | fi (customers) | xi·fi |
|---|---|---|
| 1 | 2 | 2 |
| 2 | 4 | 8 |
| 3 | 3 | 9 |
| 5 | 3 | 15 |
| — | Σf = 12 | Σ(x·f) = 34 |
Mean: μ = Σ(x·f)/Σf = 34/12 ≈ 2.833333
Dataset B — Grouped Distribution Example (Intervals)
Response times (ms) grouped into equal-width classes.
| Class [L, U) | Midpoint m | f | m·f |
|---|---|---|---|
| [0, 50) | 25 | 8 | 200 |
| [50, 100) | 75 | 14 | 1050 |
| [100, 150) | 125 | 6 | 750 |
| [150, 200) | 175 | 2 | 350 |
| — | — | Σf = 30 | Σ(m·f) = 2350 |
Approx. Mean: μ ≈ Σ(m·f)/Σf = 2350/30 ≈ 78.333333
Dataset C — Raw Data Example
Daily temperatures (°C) over a week.
| Day | xi (°C) |
|---|---|
| Mon | 28.4 |
| Tue | 31.0 |
| Wed | 29.5 |
| Thu | 30.2 |
| Fri | 27.9 |
| Sat | 26.8 |
| Sun | 29.1 |
| Σx | 202.9 |
| n | 7 |
Mean: μ = Σx/n = 202.9/7 ≈ 28.985714