Recent content by underwood

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    Hypothesis testing for 2 sample proportion

    Previously, the manager measured that the machine effectiveness was at 67.3% with a sample of size of 9. The team has made some improvements by reducing the time of changeovers, major stops and speed loss. Since those improvements, the manager has measured a rate of effectiveness at 78.2% with a...
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    How to minimize sum of probabilities coming from Z-score

    Assuming the variance to remain constant, state where the process average should be located to minimise the fraction nonconforming. What would the value of the fraction nonconforming be under these conditions? (data are normally distributed) Variance = 77.92 Upper Limit = 20 Lower Limit = 0...