Z-Score & Normal Curve - presets, bands, tails and the 68–95–99.7 rule

Load course preset	Values
	-

μ σ X two-sided (±z)
Band from z to z

Range	One-sided (μ→z)	Two-sided (±z)	Example in course
z = 0 → 1	34.13 %	68.27 %	±1 SD rule
z = 0 → 2	47.72 %	95.45 %	±2 SD rule
z = 0 → 3	49.87 %	99.73 %	±3 SD rule
z = 1 → 2	47.72 − 34.13 = 13.59 %		scores 22–25