A random sample of 225 SAT scores has a mean of 1522 Assume

A random sample of 225 SAT scores has a mean of 1522. Assume that SAT scores have a standard deviation of 300. Construct a 95% confidence interval estimate of the mean SAT scores.

Solution

A random sample of 225 SAT scores has a mean of 1522. Assume that SAT scores have a standard deviation of 300. Construct a 95% confidence interval estimate of the mean SAT scores
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x-bar = 1522
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E = 1.96*300/sqrt(225) = 39.2

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95% CI: 1522-39.2 < u < 1522+39.2