iPad '3 'FF12:22 L 'f 46% E' < m El mathxl.com C I | 1 21 2017:il: i'xii -... 'gil... 20175EE}... zl," Quizzes ... Course Ho... 8 Take a T... 19A Teleco... Homework... Triola, Essentials of Statistics 5th Edition Quiz: Assignment #4 stlbmnowz This Question: 1 pt 4 1 of 15 (0 complete) v p This Quiz: 15 pts possible Ct 19A telecommunications company wants to estimate the proportion of households that would purchase an additional telephone line if it were made available at a substantially reduced installation cost. Data are collected from a random sample of 500 households. The results indicate that 115 of the households would purchase the additional telephone line at a reduced installation cost. Complete parts (a) and (b) below. a. Construct a 95% confidence interval estimate for the population proportion of households that would purchase the additional telephone line. DSISD (Round to four decimal places as needed.) b. How would the manager in charge of promotional programs concerning residential customers use the results in (a)? O A. The manager can infer that the true population proportion of households that would purchase an additional telephone line is somewhere in this interval 95% of the time. 0 B. The manager can infer with 95% confidence that the population proportion of all households that would purchase an additional telephone line is somewhere in this interval. 0 C. The manager can infer that 95% of households would purchase an additional telephone line. 0 D. The manager can infer with 95% confidence that the proportion of households in the sample that would purchase an additional telephone line is somewhere in this interval. Click to select your answer(s). iPad '3 'FF12:23 L 'f 46% E' < > m E mathxl.com C I _(_ T 2t 2017:1l315 fxii -... E'gizi... 20172}... Ezlw Quizzes ... Course Ho... 9 Take a T... 19A Teleco... Homework... Tricia, Essentials of Statistics 5th Edition Quiz: Assignment #4 Submit Quiz This Question: 1 pt 4 4 of 15 (0 complete) v p This Quiz: 15 pts possible 0 Time spent using e-mail per session is normally distributed, with p = 10 minutes and o = 2 minutes. Assume that the time spent per session is normally distributed. Complete parts (a) through (d). a. If you select a random sample of 50 sessions. what is the probability that the sample mean is between 9.8 and 10.2 minutes? I: (Round to three decimal places as needed.) b. If you select a random sample of 50 sessions, what is the probability that the sample mean is between 9.5 and 10 minutes? I: (Round to three decimal places as needed.) c. If you select a random sample of 200 sessions, what is the probability that the sample mean is between 9.8 and 10.2 minutes? I: (Round to three decimal places as needed.) d. Explain the difference in the results of (a) and (c). Choose the correct answer below. The sample size in (c) is greater than the sample size in (a), so the standard error of the mean (or the standard deviation of the sampling distribution) in (c) is than in (a). As the standard error '1 values become '2] concentrated around the mean. Therefore, the probability of a region that includes the mean will always |:J when the sample size increases. Enter your answer in each of the answer boxes. iPad '3 'FF12:23 L 'f 46% E' < > m E mathxl.com C I _l_ 1 2t 2017:1l315 fxii -... E'gizi... 20172}... Ezlw Quizzes ... Course Ho... 9 Take a T.\" 19A Telecom Homework... Tricia, Essentials of Statistics 5th Edition Quiz: Assignment #4 Submit Quiz This Question: 1 pt 4 7 of 15 (0 complete) v p This Quiz: 15 pts possible 0 Assume that a randomly selected subject is given a bone density test. Those test scores are normally distributed with a mean of 0 and a standard deviation of 1. Find the probability that a given score is less than - 0.65 and draw a sketch of the region. Sketch the region. Choose the correct graph below. OA. QB. 06. OD. The probability is D. (Round to four decimal places as needed.) Click to select your answer(s). iPad '3 'FF12:23 L 'f 46% E' < > m E mathxl.com C I + 1 2t 2017:1l315 fxii -... E'gizi... 20172}... Ezlw Quizzes ... Course Ho... 9 Take a T... 19A Teleco... Homework... Triola, Essentials of Statistics 5th Edition Quiz: Assignment #4 Submit Quiz This Question: 1 pt 4 9 of 15 (0 complete) v p This Quiz: 15 pts possible 0 The annual ground coffee expenditures for households are approximately normally distributed with a mean of $45.18 and a standard deviation of $11.00. a. Find the probability that a household spent less than $25.00. b. Find the probability that a household spent more than $50.00. c. What proportion of the households spent between $20.00 and $30.00? d. 99.5% of the households spent less than what amount? a. The probability that a household spent less than $25.00 is D. (Round to four decimal places as needed.) b. The probability that a household spent more than $50.00 is D. (Round to four decimal places as needed.) c. The proportion of the households that spent between $20.00 and $30.00 is D. (Round to four decimal places as needed.) d. 99.5% of the households spent less than $|:|. (Round to the nearest cent as needed.) Enter your answer in each of the answer boxes. iPad '3 'FF12:23 L 'f 46% E' < > m E mathxl.com C I _l_ 1 2t 2017:1l315 fxii -... E'giii... 20172}... Ezlw Quizzes ... Course Ho... 9 Take a T... 19A Teleco... Homework... Triola, Essentials of Statistics 5th Edition Quiz: Assignment #4 Submit Quiz This Question: 1 pt 4 10 of 15 (0 complete) v p This Quiz: 15 pts possible 0 A company wants to test a randomly selected sample of n water specimens and estimate the mean daily rate of pollution produced by a mining operation. If the company wants a 90% condence interval estimate with a sampling error of 1.8 milligrams per liter (mg/L), how many water specimens are required in the sample? Assume prior knowledge indicates that pollution readings in water samples taken during a day are approximately normally distributed with a standard deviation equal to 9 mg/L. The company must sample [I water specimens in order to estimate the mean daily rate of pollution produced by a mining operation to 1.8 mg/L with 90% condence. (Round up to the nearest specimen.) Enter your answer in the answer box. iPad '3 'FF12:23 L 'f 46% E' < > m E mathxl.com C I _l_ T 2i 2017:1l315 fxii -... E'gizi... 20172}... Ezlw Quizzes ... Course Ho... 9 Take a T.\" 19A Telecom Homework... Triola, Essentials of Statistics 5th Edition Quiz: Assignment #4 Submit Quiz This Question: 1 pt 4 12 of 15 (0 complete) v p This Quiz: 15 pts possible Find the indicated 2 score. The graph depicts the standard normal distribution with mean 0 and standard deviation 1. Q 0.1736 0 z The indicated 2 score is D. (Round to two decimal places as needed.) Enter your answer in the answer box. iPad '3 'FF12:23 L 'f 46% E' < > m E mathxl.com C I _l_ T 2t 2017:1l315 fxii -... E'gizi... 20172}... Ezlw Quizzes ... Course Ho... 9 Take a T... 19A Teleco... Homework... Triola, Essentials of Statistics 5th Edition Quiz: Assignment #4 Submit Quiz This Question: 1 pt 4 13 of 15 (0 complete) v p This Quiz: 15 pts possible 0 The data below represents the overall miles per gallon (MPG) of 2008 SUVs priced under $30,000. Complete parts a and b below. 22.18.21. 20, 20, 19, 16, 16, 19, 20, 19, 1:1 16,22,19,16,17,18,17,16,19,15,22 a. Construct a 95% confidence interval estimate for the population mean miles per gallon of 2008 SUVs priced under $30,000, assuming a normal distribution. D s \"S [1 (Round to two decimal places as needed.) b. interpret the interval constructed in (a). Choose the correct answer below. O A. With 95% confidence, the mean miles per gallon in the sample of 2008 SUVs is the population mean. O B. With 95% confidence, the mean miles per gallon in the population of 2008 SUVs is somewhere in the interval. 0 C. With 95% condence, the mean miles per gallon in the sample of 2008 SUVs is somewhere in the interval. 0 D. With 95% condence, the mean miles per gallon in the population of 2008 SUVs is the sample mean. Click to select your answer(s). iPad '3 'FF12:23 L 'f 46% E' < > m E mathxl.com C I _l_ 1 2t 2017:1l315 fxii -... E'gizi... 20172}... Ezlw Quizzes ... Course Ho... 9 Take a T... 19A Teleco... Homework... Triola, Essentials of Statistics 5th Edition Quiz: Assignment #4 Submit me This Question: 1 pt El 15 of 15 (0 complete) v b This Quiz: 15 pts possible Find the area of the shaded region. The graph depicts the standard normal distribution of bone density scores with mean 0 and Q standard deviation 1. z= -0.87 z=1.26 The area of the shaded region is ]:. (Round to four decimal places as needed.) Enter your answer in the answer box.