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Standard deviation of achievement tests

The standard deviation of test scores on a certain achievement test is . A random sample of scores on this test had a mean of . Based on this sample, find a confidence interval for the true mean of all scores. Then complete the table below.
Carry your intermediate computations to at least three decimal places. Round your answers to one decimal place.

1. What is the lower limit of the 95% confidence interval? ___
2. What is the upper limit of the 95% confidence interval? ___


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