A purchasing manager at a university is investigating which brand of LCD projector to purchase to equip "smart" classrooms. Of major concern to her is the lifetime of the light bulbs used in the projectors. One company has published the following information regarding the lifetimes of a sample of so bulbs used in its LCD projectors: Frequency 15 154 12 10+ 7 5+ 3 700 750 800 850 Bulb lifetime (in hours) 900 950 1000 Based on this histogram, draw the ogive (the cumulative frequency polygon) for this company's data.

5. Suppose a marketing research firm would like to examine if the social networking site that a person primarily uses is influenced by his or her age. In a randomly drawn sample, 369 social network users were asked which site they primarily visited. These data are presented in the following table along with each person's age group. Complete parts a. through c. below. 1 Click the icon to view the data table. a. Using a = 0.025, perform a chi-square test to determine if age group and social networking site used are independent of one another. Identify the null and alternative hypotheses for a chi-square test of independence based on the information in the table. Choose the correct answer below. O A. Ho: Age group and social networking site are independent of one another. H: Age group and social networking site are not independent of one another. O B. Ho: Age group and social networking site are independent of one another. H,: The age group affects the social networking site. OC. Ho: Age…

QUESTION 2 An environmentalist wanted to determine if the mean acidity of rain differed among Ipoh, Johor Bahru and Kuantan. He randomly selected six rain dates at each city and obtained the following data: Table 2 Ipoh 5.10 5.00 4.91 5.12 4.78 5.20 Johor Bahru 4.80 4.15 4.42 4.65 4.87 4.10 Kuantan 5.45 6.23 5.55 5.10 5.42 5.25 Answer the following questions without using any output from any software. a) Construct a complete Analysis of Variance table. b) At <= 0.05, test whether the mean acidity of rain is different among the three cities. c) Based on the answer in (a) and (b), write a brief conclusion on the mean acidity of rain among Ipoh, Johor Bahru and Kuantan.

A statistics content developer at Aplia wanted to know whether study skills are related to memory quality. She invited student volunteers to perform an online memory task. The students saw a list of 60 words and were then asked to recognize a list of 10 words that were on the original list. Students were also asked to provide their GPAs.   Consider the following data set, which was collected from student volunteers in 2009. The table gives the frequency for five intervals of scores on the number of correctly identified words. Use the dropdown menus to complete the table by filling in the missing values for the proportions and percentages. Score Interval f Proportion Percentage 9–10 29 0.19 19% 7–8 53           5–6 50           3–4 22 0.14 14% 1–2 1 0.01 1%

The National Football League (NFL) records a variety of performance data for individuals and teams. To investigate the importance of passing on the percentage of games won by a team, the following data show the average number of passing yards per attempt (Yds/Att) and the percentage of games won (WinPct) for a random sample of 10 NFL teams for the 2011 season (NFL website). Team Yds/Att WinPct 5.7 26 Arizona Cardinals Atlanta Falcons Carolina Panthers 7.6 67 7.3 52 6.9 51 Chicago Bears Dallas Cowboys 5.1 17 8.6 82 New England Patriots Philadelphia Eagles Seattle Seahawks 5.3 21 6.6 41 St. Louis Rams 6.5 41 Tampa Bay Buccaneers. 6.1 38 a. Choose the correct a scatter diagram with the number of passing yards per attempt on the horizontal axis and the percentage of games won on the vertical axis. B. A. WinPct WinPct 80 DD J F1 70- 60- 50+ -40- 30 20- F2 80 F3 000 000 F4 F5 80- -70 60- 50- 40- 30- 20- S F6 ● - F7 DII F8 F9 F10 () F11 <))) F12 A