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A random sample of 400 SMC students indicated that 271 of them said they drink coffee daily  Find the 90% confidence interval for the true proportion of SMC students that drink coffee daily.  Round the endpoints of the interval to three decimal places.  Assume that the conditions to find the confidence interval are met. 

Which of the following will decrease the width of a confidence interval?

A marketing firm wants to compare the proportion of those who say they are regular viewers of reality TV in the 20-29 year and 30-39 year age groups.  In a random sample of 150 people aged 20-29, 49 said they are regular viewers of reality TV.  In a random sample of 200 people aged 30-39, 56 said they are regular viewers of reality TV.  At the 0.05 level of significance test to determine if the proportion is higher in the 20-29 age group.  Assume that the conditions to complete the hypothesis test are met.  1) What is the correct null and alternative hypothesis?  Choose from the options below.  [answer1]                                   a.     H0: 

Determine whether the sampling is independent or dependent and whether the variable is qualitative or quantitative.  A psychologist wants to measure the effect of music on relaxation.  He random selects 75 volunteers and measures their stress level in silence and then again with the same volunteers the next day while music is playing.   The mean score without music is compared to the mean score with music.

A poll was conducted asking employees and students at a large college, “Do you believe that there is enough parking available at the college?”  In a random sample of 150 employees, 87 believed that there was enough parking.  In a random sample of 320 students, 170 believed that there was enough parking.  Assume that the conditions are met to construct a confidence interval.  Choose the best answer in each case.  Where rounding is necessary round to three decimal places.  1. What is the point estimate of the difference in the proportions of employees and students that believe that there is enough parking at the college?  [pt] 2. Find the 95% confidence interval for the difference in the proportions of employees and students that believe that there is enough parking.  We are 95% confident that the difference in the proportions of employees and students that believe that there is enough parking is between [lower] and [upper]. Since the interval [is] we [conclude].

A survey of 2300 randomly chosen American Adults found that 604 agreed that they had experienced insomnia in the last month.  Use this information to complete the following to find the corresponding 95% confidence interval. a. What is the point estimate of the proportion of American Adults that have experienced insomnia in the last month?  Round to three decimal places.  [answera] b. Does the sample meet the conditions to calculate the confidence interval for the proportion?           [answerb] because the sample is random, the sample is less than 5% of the population and [answerc]. c.  Use the appropriate formula to find the margin of error, rounded to three decimal places.  Remember to round off only at the end.  [answerd] d. Using the margin of error and point estimate from the above questions, find the 95% confidence interval for the proportion of American Adults who have experienced insomnia in the last month.  Round to three decimal places.  Choose the best answer.   [answere]  

A city wants to determine the mean amount that residents pay in property taxes each year. At least how many residents should be polled to determine the mean property tax to within $2000 at 95% confidence? Assume that the city has estimated the standard deviation in property tax paid to be $35000.  

Suppose you want to find a confidence interval at a confidence level of 88%. What is the corresponding critical value,

Suppose you want to test the claim that μ < 35.7. Given a sample size of n = 31 and a level of significance ofα = 0.10, when should you reject the null hypothesis ?

Researchers wanted to see if there was a difference between students and faculty attitudes at the college level toward the use of cell phones in class.  Among the 580 students polled, 190 said that using a cell phone in class distracted from learning, among 600 faculty polled 238 said that using a cell phone in class distracted from learning.  At the 0.05 level of significance, test the claim that the proportion of students who said that using a cell phone in class distracted from learning was lower than the proportion of faculty. You may assume that the sample meets the necessary conditions to conduct the hypothesis test.    1) What is the correct null and alternative hypothesis?  Choose from the options below.  [answer1]                                   a.     H0: