A random sample of 16 customers at a Supermarket showed that the mean time spent waiting in line to be served at the counter was 31 minutes with a standard deviation of 7 minutes. Construct a 90% confidence interval for the mean time spent waiting in line by all customers at this supermarket. Assume that such waiting times for all customers are normally distributed.
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Given that the critical value for a 90% confidence interval with 15 degrees of freedom is 1.753, and the sample standard deviation is 7, we can calculate the margin of error using the formula: Margin of error = Critical value * (Standard deviation / sqrt(sample Show more…
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