sag own @i ' O Question8 v ' l ' 80/5 pts '0 20 8 99 G Details A researcher is interested in finding a 99% confidence interval for the mean number of times per day that college students text. The study included 143 students who averaged 39.8 texts per day. The standard deviation was 24.4 texts. Round answers to 3 decimal places where possible. a. To compute the confidence interval use a '2 a distribution. b. With 99% confidence the population mean number of texts per day is between [3 and [3 texts. c. If many groups of 143 randomly selected members are studied, then a different confidence interval would be produced from each group. About C] percent of these confidence intervals will contain the true population number of texts per day and about [:] percent will not contain the true population mean number of texts per day. Question Help: Q Written Example 8 Message instructor Submit Question Jump to Answer M E dmyopenmathmm '0 1 [1'1 ' ii] ' 0 Question 9 v l l ' B 0/5 pts '0 20 Z 99 G) Details You are interested in finding a 95% confidence interval for the average number of days of class that college students miss each year. The data below show the number of missed days for 15 randomly selected college students. Round answers to 3 decimal places where possible. mam-Innnnnnmnnu a. To compute the confidence interval use a ? a distribution. b. With 95% confidence the population mean number of days of class that college students miss is between and Dm- C. If many groups of 15 randomly selected non-residential college students are surveyed, then a different confidence interval would be produced from each group. About [:] percent of these confidence intervals will contain the true population mean number of missed class days and about C] percent will not contain the true population mean number of missed class days. Question Help: [Q Written Example 8 Message instructor Submit Question Jump to Answer d myopenmathcom 0 Question 10 v I ' I Aisha wants to advertise how many chocolate chips are in each Big Chip cookie at her bakery. She randomly selects a sample of 78 cookies and finds that the number of chocolate chips per cookie in the sample has a mean of 10.1 and a standard deviation of 3.5. What is the 99% confidence interval for the number of chocolate chips per cookie for Big Chip cookies? Assume the data is from a normally distributed population. Round answers to 3 decimal places where possible. [:wD Question Help: @ Written Example 8 Message instructor Submit Question Jump to Answer : myopenmathlcom ' 0 Question 11 v r ' I You want to obtain a sample to estimate a population mean. Based on previous evidence, you believe the population standard deviation is approximately a = 73.5. You would like to be 95% confident that your estimate is within 3 of the true population mean. How large of a sample size is required? Round up to nearest whole number. at] Question Help: IE] Video [Q Written Example 8 Message instructor ,, Submit Question Jump to Answer 0 Question 12 v ' '