he formula used to calculate a confidence interval for the mean of a normal population is x ± (t critical value) s   n. What is the appropriate t critical value for each of the following confidence levels and sample sizes? (Use a table or technology. Round your answers to two decimal places.) (a) 90% confidence,  n = 12   (b) 90% confidence,  n = 27   (c) 95% confidence,  n = 11

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Q: Find a 95% confidence interval for a mean, µ, where n = 324, x̄ = 2.7, s = .91, and se = .06.

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Q: f n=18, x = 33, and s = 8, find the margin of error at a 80% confidence level Give your answer to…

A: Given data n = 18 x =33, s= 8 Confidence level c = 0.8 α = 1- 0.8 = 0.2

Q: What is the appropriate critical t at the 90% confidence level?

A: From the given information, the confidence level is 0.9.