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Statistics & DataEasyBinomial and Geometric

Binomial and Geometric · Easy problem

A binomial count XX has success probability p=0.25p = 0.25. The normal approximation to XX is considered safe when both np≥10np \ge 10 and n(1−p)≥10n(1-p) \ge 10. What is the smallest number of trials nn for which both conditions hold?