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Sample Size Calculator
Determine the required sample size for a study given confidence level, margin of error, and standard deviation.
Required Sample Size
16
Confidence Level
95%
Z-Score
1.9600
Margin of Error
5%
Std Deviation
10.0000
Formula
n = (z · σ / E)²
n = (1.9600 · 10.0000 / 5)² = 16
You need a sample of at least 16 subjects to estimate the population mean with 95% confidence and a 5% margin of error.