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Based on the measurements of 36 randomly selected textbooks with a mean weight of 38 ounces and a population standard deviation of 6.2 ounces, please construct a 95% confidence interval for what parameter or characteristic.

User MrPatterns
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Final answer:

To construct a 95% confidence interval for the population mean weight of 36 textbooks, use the formula with the given mean, population standard deviation, and Z-score for 95% confidence. The interval will be 35.98 ounces to 40.02 ounces.

Step-by-step explanation:

Based on the measurements of 36 randomly selected textbooks with a mean weight of 38 ounces and a population standard deviation of 6.2 ounces, we can construct a 95% confidence interval for the population mean weight of the textbooks. Since the population standard deviation is known, we use the normal distribution to construct this interval.

To calculate the 95% confidence interval, we need to use the formula for the confidence interval of a population mean with a known standard deviation:

Confidence Interval = Sample Mean ± (Z-score * (Population Standard Deviation / sqrt(n)))

Here, sqrt(n) stands for the square root of the sample size, and the Z-score is the value from the standard normal distribution that corresponds to the desired level of confidence. For a 95% confidence level, the Z-score is typically 1.96.

Therefore, the confidence interval for the population mean weight of the textbooks is:

38 ± (1.96 * (6.2 / sqrt(36)))

After calculating the margin of error:

38 ± (1.96 * (6.2 / 6)) = 38 ± 2.02

The 95% confidence interval is therefore 35.98 ounces to 40.02 ounces.

User Rokia
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