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Find the probability of at least 6 failuresin 7 trials of a binomial experiment inwhich the probability of success in anyone trial is 9%.p=[?1%Round to the nearest tenth of a percent.

User Folasade
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\begin{gathered} The\text{ binomial probability distribution is given in the following form:} \\ P\text{ = nCx \lparen p}^x)(q^(n-x)) \\ Finding\text{ the probability of at least 6 failures means the probability of 6 or 7 failures.} \\ This\text{ corresponds to 1 or 0 successes.} \\ P(1)\text{ = 7C1 \lparen9\%}^1)(91\%^6) \\ \text{ =0.3278} \\ P(0)\text{ = 0.5168} \\ Probability\text{ of at most one success \lparen at least 6 failures\rparen} \\ =\text{ 0.844 = 84.5\%} \end{gathered}

User Eric Brandwein
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