Distributions Lab
Compute binomial probabilities, standardize with z-scores, and use the empirical rule and normal tables.
1 Normal curve explorer
Slide μ and σ to reshape the bell; shade regions and read their probabilities.
Shaded area: –
z(a): –
2 What to notice
- Bigger σ flattens and widens the bell — but total area stays 1.
- Shade “within 2σ” and read ≈0.95: the empirical rule, live.
- Moving μ slides the curve without changing its shape — z-scores measure position in σ-units.