Exercise 91? [L093] The Fox T'v' network is considering replacing one of its prime-time crime investigation shows with a new femilycented comedy show. Before a nal decision is made, network executives commission e sample of 50!] viewers. After viewing the comedy, 15D indicated theyr would watch the new show and suggested it replace the crime investigation show. Estimate the value of the population proportion. [Round the z-values to 2 decimal places. Round a. your answer to 3 decimal places.) comm... E b. Develop a 90% corrlidence interval for the population proportion. {Use 2 Distribution Tabla.) {Round the z-values to 2 decimal places. Round your answers to 3 decimal places.) mum Ema:- Exercise 9-4? [LOB-31 Fashion Industries randomly tests its employees throughout the year. Last year in the 5-40 random tests learinduotedr 22 employees failed the test. [Use 2 Distribution Table.) 1. Develop a 90% oondenee interval for the proportion of employees that fail the test. [Round the :- 1ll'alues to 2 decimal places. Round your answers to 3 decimal places.) Condel'loeinhwalisbelmm and . 2. Would itbe reasonable to eonolude that less than 5% of the employees are not able to pass the random dmg test? Exercise $53 {LOB-4) The proportion o'f public accountants who have changed companies within the last three years is to be estimated within 4%. The 90% level of condence is to be used. Astudy conducted several years ago revealed that the percent of public accountants changing companies within three yearswas 22. (Use ; Distribution Tabla.) {Round the z-Jvalues to 2 decimal places. Round up your answers to the next whole number.) a. To update this study. the les of how many public accountants should be studied? b. Hornr many public accountants should be contacted if no previous estimates of the population proportion are available? '_ Exercise 9-51 (Lee-4) A survey of 23 randomly selected 'iPhone\" owners showed that the purchase price has a mean of $426 with a sample standard deviation of 5165. (Use t Distribution Table.) a. Compute the standard error of the sample mean. [Round your answer to the nearest whole number.) 5...... m E b. Compute the 95% condence interval for the mean. [Ron nd your answers to 3 decimal places] The conde-res interval is between and . e. To be 95% oondent, hoilllr large a sample is needed to estimate the population mean within 514? [Ron ndup your answer to the next whole number.) we E Exercise 9-50 {LOB-3) In a poll to estimate presidential popularity, each person in a random sample of 1,350 voters was asked to agree with one of the following statements: '1. The president is doing a good job. 2. The president is doing a poorjob. 3. I have no opinion. Atotal of 550 respondents selected the rst statement. indie-ting they thought the president was doing a good job. a. Construot a 95% oondenoe interval for the proportion of respondents who feel the president is doing a goodjob. (Use 2 Distribution Tabla.) [Round your answers to 3 decimal places.) Gon'liderne inhrval forthe proportion is up to b. Based on your interval in pert (a). is it reasonable to conclude that a majority ofthe population believes the president is doing a good job? ('2' No 0 Yes Exercise 954 {L094} You need to estimate the mean number of travel days per year for outside salespeople. The mean of a small pilot study was 150 days, with a standard deviation of 4C! days. if you must estimate the population mean within 4 days, hDW manglr outside salespeople should you sample? Use the 95% condence level. {Use 2 Dishibution Tabla.) {Round up your aruwer to the next whole numbers} Number of outside salespeople Exercise 9-44 [L092] The manufacturer of a new line of ink-jet printers would like to include as part of its advertising the number of pages a user can expect from a print cartridge. A sample of 1D cartridges revealed the following number of pages printed. [Use t Distribution Table.) 2,111!) 2,560 2,550 2,610 2,!320 2,!310 2,330 3,430 2,620 3.1?!) a. What is the point estimate 0'! ihe population mean? {Round your answer to the nearest whole number.) Es'li'nmd popuiaon mean |:| b. Develop a 959i: mndenoe interval for the population mean. [Round your answers to 2 decimal places.] Conderneinhwaiformepopulaonmeanisbaiween |:| and E. Exercise 943 (Lose) Warren Gountyr Telephone Company claims in its annual report that \"the typical customer spends $61 per month on local and longdistance ser'isice.'I A sample of 12 subscribers revealed the following amounts spent last month. $55 $65 $64 $6? $5? $53 $158 $53 $64 $53 $54 $53 a. What is the point estimate of the population mean'?I (Round your answer to ll decimal places.) assumed populaEen mean s '_ b. Develop a 99% condence interval for the population mean. {Use t Distribution Table.) (Round your answers to 3 decimal places.) Condence interval torthe population mean $ = II and $ I o. Is the oompany's claim that the ltypioal customer" spends $61 per month reasonable? If) Yes '3 No Exercise 9*54 (LEE-IQ} As part of an annual revievtr of its accounts. a discount brokerage selects a random sample of 28 customers. Their accounts are reviewed for total account valuation. which showed a mean of$34,m. with a sample standard deviation of $8.400. [Use t Distribution Tabla] What is a 93% condence interval for the mean account valuation of the population of customers? I: Round your answers to the nearest dollar amount] msmmnnrmamammmms |:|ands |:|. Exercise 9-3 [LO'EFZJ A sample 01' 24B ehservaiiens is selected from a nerrnal pepulaen for which Ihe pepulaiien standard deviaiien is knew to be 21. The sample mean is 25. a. Determine Ihe standard error ef the mean. [Round yeur answer in 3 decimal places.) Shndardeneref'lernem |:| 1:. Determine Ih-e 93% senlidense interval far he papulaiien mean. {Use 2 Distribution Table.) [Round your answers in 3 decimal places] mar-mm Em: \f\fExercise 954 {L094} You need to estimate the mean number of travel days per year for outside salespeople. The mean of a small pilot study was 150 days, with a standard deviation of 4C! days. if you must estimate the population mean within 4 days, hDW manglr outside salespeople should you sample? Use the 95% condence level. {Use 2 Dishibution Tabla.) {Round up your aruwer to the next whole numbers} Number of outside salespeople Exercise 9-44 [L092] The manufacturer of a new line of ink-jet printers would like to include as part of its advertising the number of pages a user can expect from a print cartridge. A sample of 1D cartridges revealed the following number of pages printed. [Use t Distribution Table.) 2,111!) 2,560 2,550 2,610 2,!320 2,!310 2,330 3,430 2,620 3.1?!) a. What is the point estimate 0'! ihe population mean? {Round your answer to the nearest whole number.) Es'li'nmd popuiaon mean |:| b. Develop a 959i: mndenoe interval for the population mean. [Round your answers to 2 decimal places.] Conderneinhwaiformepopulaonmeanisbaiween |:| and E. Exercise 943 (Lose) Warren Gountyr Telephone Company claims in its annual report that \"the typical customer spends $61 per month on local and longdistance ser'isice.'I A sample of 12 subscribers revealed the following amounts spent last month. $55 $65 $64 $6? $5? $53 $158 $53 $64 $53 $54 $53 a. What is the point estimate of the population mean'?I (Round your answer to ll decimal places.) assumed populaEen mean s '_ b. Develop a 99% condence interval for the population mean. {Use t Distribution Table.) (Round your answers to 3 decimal places.) Condence interval torthe population mean $ = II and $ I o. Is the oompany's claim that the ltypioal customer" spends $61 per month reasonable? If) Yes '3 No Exercise 9*54 (LEE-IQ} As part of an annual revievtr of its accounts. a discount brokerage selects a random sample of 28 customers. Their accounts are reviewed for total account valuation. which showed a mean of$34,m. with a sample standard deviation of $8.400. [Use t Distribution Tabla] What is a 93% condence interval for the mean account valuation of the population of customers? I: Round your answers to the nearest dollar amount] msmmnnrmamammmms |:|ands |:|. Exercise 9-3 [LO'EFZJ A sample 01' 24B ehservaiiens is selected from a nerrnal pepulaen for which Ihe pepulaiien standard deviaiien is knew to be 21. The sample mean is 25. a. Determine Ihe standard error ef the mean. [Round yeur answer in 3 decimal places.) Shndardeneref'lernem |:| 1:. Determine Ih-e 93% senlidense interval far he papulaiien mean. {Use 2 Distribution Table.) [Round your answers in 3 decimal places] mar-mm Em: \f\f