StatisticValue
Standard Deviation (σ)4.47038869
Count (N)8
Sum (Σx)133
Mean (μ)16.62500000
Variance (σ²)19.98437500

Calculation Steps:

Variance (σ²):
σ² = [(11 - 16.62500000)² + (9 - 16.62500000)² + (21 - 16.62500000)² + (21 - 16.62500000)² + (17 - 16.62500000)² + (21 - 16.62500000)² + (19 - 16.62500000)² + (14 - 16.62500000)²] / 8
= 159.87500000 / 8
= 19.98437500

Standard Deviation (σ):
σ = √19.98437500
= 4.47038869