Appendix A.25
Normal Approximation to Binomial
Use the normal distribution to approximate binomial probabilities with continuity correction.
Normal Approximation Calculator
Approximation Valid
≥ 10
Parameters
μ = np:20.00
σ = √np(1-p):3.4641
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Exact Binomial
0.561035
Normal Approximation
0.557383
Continuity Correction Applied
For P(X ≤ 20), we use P(X < 20.5). Z = (20.5 - 20.00) / 3.46 = 0.1443