1. A tire manufacturer determines at what temperature the tires will tend to bubble. In a...

1. A tire manufacturer determines at what temperature the tires will tend to bubble. In a sample of 21 tires, the mean temperature was 120 degrees F. with a standard deviation of 12 degrees. Construct the 98% confidence interval for the population mean.

2. The standard deviation of the length of 31 steel rods that are cut to be 3 feet is 0.023 feet. What is the 80% confidence interval for the population variance and the standard deviation?

3. In a sample of 450 bottles in a bottling plant, 12 bottles were incorrectly capped. Construct a 96% confidence interval for the proportion of bottles that are incorrectly capped.

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orchestra answered 2 years ago

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