Current Attempt in Progress Number of Text Messages a Day A random sample of n = 755 US cell phone users age 18 and older in May 2011 found that the average number of text messages sent or received per day is 41.5 messages, with standard error about 6.1. 1Smith, A., "Americans and Text Messaging," Pew Research Center, http://www.pewinternet.org/Reports/2011/Ce Phone-Texting-2011/Main-Report/How- Americans-Use-Text-Messaging.aspx, accessed September 19, 2011.8 of 13 - /12 E ... the average number of text messages sent or received per day is 41.5 messages, with standard error about 6.1. 1Smith, A., "Americans and Text Messaging," Pew Research Center, http://www.pewinternet.org/Reports/2011/Cell- Phone-Texting-2011/Main-Report/How- Americans-Use-Text-Messaging.aspx, accessed September 19, 2011. Part 1 (a) Use the information from the sample to give the best estimate of the population parameter. X = 1- Lesson 4 WileyPLUS 8 of 13 > - /12 E . . . Part 2 (b) Find a 95 % confidence interval for the mean number of text messages. The 95 % confidence interval is to eTextbook and Media Hint Save for Later Attempts: unlimited Submit Answer Question Part Score --/65:30 .1 5G 0 / 12 E . . . College Graduates 27.5 % of US adults are college graduates. Click here to access StatKey. Round your answers to three decimal places. (a) Use StatKey or other technology to generate a sampling distribution for the sample proportion of college graduates using a sample size of n = 50. Generate at least 1000 sample proportions. Give the center of the sampling distribution and give the standard error. Center = 0.63 Standard error =0.63 Standard error = 0.020 (b) Repeat part (a) using a sample size of n = 500. Center = 29.544 Standard error = 53.456 e Textbook and Media Hint Save for Later