# Increase the sample size correct increasing the

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Increase the sample size CORRECT Increasing the sample size provides a more accurate representation of the population and therefore, reduces the width of the confidence interval. Note that another option is also correct.
Decrease the sample size Decreasing the sample size can lead to less accurate results and therefore, increases the width of the confidence interval.
Increasing the confidence level increases the width of the confidence interval.
Increasing the mean does not necessarily reduce the width of the confidence interval. The mean affects the center of the confidence interval but does not affect the width.
10) A streaming music site changed its format to focus on previously unreleased music from rising artists. The site manager now wants to determine whether the number of unique listeners per day has changed. Before the change in format, the site averaged 131,520 unique listeners per day. Now, beginning three months after the format change, the site manager takes a random sample of 30 days and finds that the site has an average of 124,247 unique listeners per day. SELECT THE TWO ANSWERS below that represent the correct null and alternative hypotheses. μ=124,247 μ=124,247 The null and alternative hypotheses are always based on historical information. μ≠124,247 μ≠124,247 The null and alternative hypotheses are always based on historical information. μ≥124,247 μ≥124,247 The null and alternative hypotheses are always based on historical information. μ≤124,247 μ≤124,247 The null and alternative hypotheses are always based on historical information. μ=131,520 μ=131,520 CORRECT The null hypothesis is that number of unique listeners per day has not changed. Thus, μ=131,520 μ=131,520 is the null hypothesis. μ≠131,520 μ≠131,520 CORRECT The alternative hypothesis is that the number of unique listener per day has changed. Thus, μ≠131,520 μ≠131,520 is the alternative hypothesis. μ≥131,520 μ≥131,520 The owner wants to test for a change in either direction. Thus, this option can be neither the null nor the alternative hypothesis. μ≤131,520 μ≤131,520 The owner wants to test for a change in either direction. Thus, this option can be neither the null nor the alternative hypothesis.
11) A streaming music site changed its format to focus on previously unreleased music from rising artists. The site manager now wants to determine whether the number of unique listeners per day has changed. Before the change in format, the site averaged 131,520 unique listeners per day. Now, beginning three months after the format change, the site manager takes a random sample of 30 days and finds that the site now has an average of 124,247 unique listeners per day. Using