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Slide 2 What Is The Average Hours You Spend On Your Phone Daily? Cristian Barrios Jacky Cortez Maria Canongo Period 2 Year (2011-2012) Slide 3 8.0 Students organize and describe distributions of data by using a number of different methods, including frequency tables, histograms, standard line and bar graphs, stem- and-leaf displays, scatter plots, and box-whisker plots. 17.0 Students determine confidence intervals for a simple random sample from a normal distribution of data and determine the sample size required for desired margin of error. 18.0 Students determine the P - value for a statistic for a simple random sample from a normal distribution. Slide 4 We believe that the average hours centurions spend on their phone is 3 hours. Slide 5 We are using cluster sampling by asking only seniors. Example: we will collect data by using the cluster method technique by asking them how many hours they spend on their phones per day. Two of us asked 13 senior students, and one of us asked 14 senior students equaling a total of 40 seniors at Century High School. Slide 6 Number of hours. 3, 2, 1,.5,.5, 2, 8, 4, 12, 1.5, 10, 6, 12, 5, 20, 1, 1, 2, 4, 13, 12, 8, 6, 12, 7, 14, 18, 8, 12, 3, 20, 14, 10, 9, 11, 10, 4, 14, 12, 12 Slide 7 Slide 8 Slide 9 95% Confidence IntervalZ-Interval(6.3306,9.6944) We are 95% confident that the population mean for all senior students is between 6.33 and 9.69 hrs. Slide 10 Step I Hypothesis Claim: We believe that the average hours centurions spend on their phone is 3 hours. H o : = 3(claim) H a : > 3 Step II Test Statistics P-value: 5.19 x 10 -9 Step III Conclusion At 5% level of significance, we failed to reject. There is enough evidence to support our claim. Slide 11 Our sample mean is 8.01 hours, and the 95% confidence level for the population mean is between 6.3 to 9.7 hours. The marginal error is about 2 hours. Our sample error is due to possible under- representation of the population. We might need to take more samples due to students that have phones, and those who dont. Slide 12 We hypothesized that Century seniors commute time average is 3 hrs. In our survey of 40 seniors, we found the sample mean of 8.0125 hrs., with standard deviation of 5.4272 hrs. We conclude that the population mean for the seniors students is between (6.3306,9.6944)hrs with 95% confident. We tested our initial hypothesis with 5% level of significance, and found out our hypothesis was incorrect.