Question 950125
The sampled population is normally distributed, with the given information. (Give your answers correct to two decimal places.) 
n = 13, x-bar = 28.3, and σ = 6 
(a) Find the 0.9 confidence interval for μ.
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sample mean:: 28.3
ME = 1.645*6/sqrt(13) =2.7372
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90% CI:: 28.3-2.7372 < u < 28.3+2.7372
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(b) Are the assumptions satisfied?
I'll leave that to you. Check your textbook.
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Cheers,
Stan H.