The distribution of grades is know to follow a normal distribution, but the mean and variance are unknown. A random sample of 12 students produced the following scores:(adsbygoogle = window.adsbygoogle || []).push({});

59, 84, 68, 93, 49, 77, 82, 75, 81, 58, 70, 80

Find the 90% two-sided confidence interval for the mean score.

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# Find the 90% two-sided confidence interval for the mean score.

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