# Question

Use the sample information x-bar = 37, σ = 5, n = 15 to calculate the following confidence intervals for assuming the sample is from a normal population:

(a) 90 percent confidence;

(b) 95 percent confidence;

(c) 99 percent confidence.

(d) Describe how the intervals change as you increase the confidence level.

(a) 90 percent confidence;

(b) 95 percent confidence;

(c) 99 percent confidence.

(d) Describe how the intervals change as you increase the confidence level.

## Answer to relevant Questions

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