Formula:
CI90 = mean + or - 1.645(sd divided by √n)
...where + or - 1.645 represents the 90% confidence interval using a z-table, sd = standard deviation, √ = square root, and n = sample size.
With your data:
CI90 = 22 + or - 1.645(2.4/√37)
I'll let you take it from here.
A researcher randomly selects 37 subjects and administers an attitude test regarding a product. Their mean is 22 and their standard deviation is 2.4. Construct the 90% confidence interval for the mean score of all such subjects
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