The standard deviation of test scores on a certain achievement test is 10.5 . A random sample of 100 scores on this test had a mean of 75.7 . Based on this sample, find a 90% confidence interval for the true mean of all scores. Then give its lower limit and upper limit. Carry your intermediate computations to at least three decimal places. Round your answers to one decimal place. upper limit ? lower limit?

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Estimation

A new framework of data analysis where the new statistical methods are used for interpreting the results and analyzing the data is known as estimation in statistics.