52 CHAPTER 2 Exploring Data with Tables and Graphs 7. Blood Platelet Count of Males Frequency 0–99 1 100–199 51 200–299 90 300–399 10 400–499 0 500–599 0 600–699 1 8. Blood Platelet Count of Females Frequency 100–199 25 200–299 92 300–399 28 400–499 0 500–599 2 In Exercises 5–8, identify the class width, class midpoints, and class boundaries for the given frequency distribution. Also identify the number of individuals included in the summary. The frequency distributions are based on real data from Appendix B. 5. Age (yr) of Best Actress When Oscar Was Won Frequency 20–29 31 30–39 34 40–49 15 50–59 3 60–69 6 70–79 1 80–89 1 6. Age (yr) of Best Actor When Oscar Was Won Frequency 20–29 1 30–39 29 40–49 38 50–59 16 60–69 6 70–79 1 Normal Distributions. In Exercises 9–12, using a loose interpretation of the criteria for determining whether a frequency distribution is approximately a normal distribution, determine whether the given frequency distribution is approximately a normal distribution. Give a brief explanation. 9. Best Actresses Refer to the frequency distribution from Exercise 5. 10. Best Actors Refer to the frequency distribution from Exercise 6. 11. Blood Platelet Counts of Males Refer to the frequency distribution from Exercise 7. 12. Blood Platelet Counts of Females Refer to the frequency distribution from Exercise 8. Constructing Frequency Distributions. In Exercises 13–20, use the indicated data to construct the frequency distribution. (The data for Exercises 17–20 can be downloaded at TriolaStats.com.) 13. Chicago Commute Time Listed below are the first 50 Chicago commute times from Data Set 31. Construct a frequency distribution. Use a class width of 15 minutes and begin with a lower class limit of 0 minutes. Do the data amounts appear to have a normal distribution? Examine the data and identify anything appearing to be unique. 60 15 35 30 15 45 10 15 15 30 12 30 30 45 30 20 20 15 25 45 60 15 28 30 30 60 30 45 30 12 45 20 10 15 45 45 35 60 20 20 2030 4 80453060452530 Height (cm) Relative Frequency 130–144 23% 145–159 25% 160–174 22% 175–189 27% 190–204 28% Table for Exercise 4 4. What’s Wrong? Heights of adult males are known to have a normal distribution, as described in this section. A researcher claims to have randomly selected adult males and measured their heights with the resulting relative frequency distribution as shown in the margin. Identify two major flaws with these results.
RkJQdWJsaXNoZXIy NjM5ODQ=