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In: Statistics and Probability

A local retailer claims that the mean waiting time is less than 8 minutes. A random...

A local retailer claims that the mean waiting time is less than 8 minutes. A random sample of 20 waiting times has a mean of 6.8 minutes with a standard deviation of 2.1 minutes. At a = 0.01, test the retailer's claim. Assume the distribution is normally distributed. Round the test statistic to the nearest thousandth.

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Solution:-

T-test statistic = −2.556


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