A doctor wants to estimate the mean HDL cholesterol of all 20-to 29-year-old females. How many subjects are needed to estimate the mean HDL cholesterol within 3 points with \( 99 \% \) confidence assuming s = 12.9 based on earlier studies? Suppose the doctor would be content with \( 90 \% \) confidence. How does the decrease in confidence affect the sample size required? Click the icon to view a partial table of critical values. A. Decreasing the confidence level decresases the sample size needed. B. Decreasing the confidence level increases the sample size needed. C. The sample size is the same for all levels of confidence.

In how many ways can a committee of 5 students be formed from 10 students?

Find the range of the following data set, Assume the data set is a sample. \[ \begin{array}{lllllllllll} & 41 & 82 & 37 & 43 & 77 & 44 & 44 & 50 & 49 & 49\end{array} \] 8

A water bottling facility has a mean bottling rate of 33.5 thousand bottles per hour with a standard deviation of 1.92 thousand bottles. A nearby cola bottling facility has a mean bottling rate of 26.2 thousand bottles per hour with a standard deviation of 1.42 thousand bottles. One Wednesday from noon to \( 1: 00 \) p.m., the water bottling facility bottled 36.8 thousand bottles of water, and the cola bottling facility bottled 28.4 thousand bottles of cola. Which facility increased their efficiency more during that hour? Answer

Scores on a test have a mean of 78 and a standard deviation of 13 . Tom has a score of 66 . Convert Tom's score to a \( z \)-score, rounded to the nearest hundredth.

Identify the population, the sample, and any population parameters or sample statistics in the given scenario. In the 1960 s, a poll of 2617 homeowners in the United States resulted in a report that the average price of a house in the U.S. was \( \$ 18,500 \). Answer O Population: none given: Sample: 2617 homeowners polled: Sample Statistic: \( \$ 18,500 \) Opopulation: U.S. homeowners: Sample: none given; Population Parameter: \( \$ 18,500 \)