# Comparisons Between Confidence Interval Estimates

The overall miles per gallon (MPG) of 2009 Sedans priced under $20,000.

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(a) Construct a 95% confidence interval estimate for the population mean MPG of 2009 Sedans (4 cylinder) priced under $20,000, assuming normal distribution.

(b) Interpret the interval constructed in (a).

(c) Compare the results in (a) to those in following problem:

Construct a 95% confidence interval estimate for the population mean MPG of 2009 SUVs priced under $30,000, assuming normal distribution

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https://brainmass.com/statistics/confidence-interval/comparisons-between-confidence-interval-estimates-527047

#### Solution Preview

Problem: The attached file (Sedans) contains the overall miles per gallon (MPG) of 2009 priced under $20,000.

27 31 30 28 27 24 29 32 32 27 26 26 25 26 25 24

(a) Construct a 95% confidence interval estimate for the population mean MPG of 2009 sedans (4 cylinder) priced under $20,000, assuming normal distribution.

(b) Interpret the interval constructed ...

#### Solution Summary

The comparisons between confidence interval estimates are determined.