A soccer ball manufacturer wants to estimate the mean circumference of soccer balls within 0.05 in. (a) Determine the minimum sample size required to construct a 90% confidence interval for the population mean. Assume the population standard deviation is 0.20 in. (b) Repeat part (a) using a population standard deviation of 0.40 in. Which standard deviation requires a larger sample size? Explain.
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A soccer ball manufacturer wants to estimate the mean circumference of soccer balls within 0.05 in. (a) Determine the minimum sample size required to construct a 90% confidence interval for the population mean. Assume the population standard deviation is 0.20 in. (b) Repeat part (a) using a population standard deviation of 0.40 in. Which standard deviation requires a larger sample size? Explain.
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