statistics

A simple random sample of 40 items resulted in a sample mean of 25. The population standard deviation is 5.
a. What is the standard error of the mean (to 2 decimals)?
b. At 95% confidence, what is the margin of error (to 2 decimals)?

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  1. Part a)
    SE of mean = sd/√n = 5/√40

    Part b)
    ME = 1.96 * 5/√40

    I'll let you finish the calculations.

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  2. .80

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  3. A) 0.79
    B) 1.55

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