Answer Happy

The table below contains a certain social media company's penetration values (the percentage of a country's population that use this social media) for 14 countries. Complete parts a through c below. 14 48 21 28 a. Construct a 95% confidence interval estimate for the population mean social media penetration. The 95% confidence interval estimate is from 22.21 to 44.08. (Round to two decimal places as needed.) b. What assumption do you need to make about the population distribution to construct the interval in (a)? Choose the correct answer below. 15 15 83 56 29 36 26 23 40 30 D O A. The social media penetration follows the t distribution. OB. The populations of the sampled countries follow the t distribution. ✓ Q ✩ A cellphone provider has the business objective of wanting to estimate the proportion of subscribers who would upgrade to a new cellphone with improved features if it were made available at a substantially reduced cost. Data are collected from a random sample of 500 subscribers. The results indicate that 130 of the subscribers would upgrade to a new cellphone at a reduced cost. Complete parts (a) and (b) below. Screen Shot 2022-07-10 at 12.53.46 PM ✓ ☹ Q Search a. Construct a 95% confidence interval estimate for the population proportion of subscribers that would upgrade to a new cellphone at a reduced cost. 0.2215 ≤x≤ 0.2984 (Round to four decimal places as needed.) b. How would the manager in charge of promotional programs use the results in (a)? A. The manager can infer that the true population proportion of subscribers that would upgrade to a new cellphone at a reduced cost is somewhere in this interval 95% of the time. OB. The manager can infer with 95% confidence that the population proportion of all subscribers that would upgrade to a new cellphone at a reduced cost is somewhere in this interval. OC. The manager can infer that 95% of subscribers that would upgrade to a new cellphone at a reduced cost. O D. The manager can infer with 95% confidence that the proportion of subscribers in the sample that would upgrade to a new cellphone at a reduced cost is somewhere in this interval. The following data are the amounts that a sample of 15 customers spent for lunch ($) at a fast-food restaurant. Complete parts (a) through (d) below. 5.95 7.48 6.32 5.80 6.54 8.30 9.51 7.07 6.81 4.87 6.52 5.52 7.93 8.30 9.66 a. Construct a 95% confidence interval estimate for the population mean amount spent for lunch ($) at a fast-food restaurant. 6.32 sus 7.89 (Round to two decimal places as needed. Do not include the $ symbol in your answer.) b. Interpret the interval constructed in (a). Choose the correct answer below. O A. The mean amounts in dollars spent for lunch at the fast-food restaurant of 95% of all samples of the same size are contained in the interval. O B. Conclude with 95% confidence that the mean amount in dollars spent for lunch at the fast-food restaurant for the sample is contained in the interval. OC. Conclude with 95% confidence that the population mean amount in dollars spent for lunch at the fast-food restaurant is contained in the interval. O D. 95% of the sample data fall between the limits of this confidence interval.