# Chapter 7 - Estimates and Sample Sizes - 7-3 Estimating a Population Mean - Basic Skills and Concepts - Page 356: 4

When we say that the confidence interval methods of this section are robust against departures from normality, it means that the methods work well with distributions that are not normal, provided that departures from normality are not too extreme. The given dotplot satisfies the loose normality requirement. Since there are 40 dots, the sample size of 40 satisfies the condition of n > 30.

#### Work Step by Step

When we say that the confidence interval methods of this section are robust against departures from normality, it means that the methods work well with distributions that are not normal, provided that departures from normality are not too extreme. The given dotplot satisfies the loose normality requirement. Since there are 40 dots, the sample size of 40 satisfies the condition of n > 30.

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