A study is done to compare the mean cost of tuition at a state college in New York and California.  In New York the sample mean annual tuition is found to be $20,956 and in California the sample mean annual tuition is found to be $17,753.  The 95% confidence interval for the mean tuition in New York is ($18,616; $23,296).  The 95% confidence interval for California is ($15,413; $20,093).   Which of the following statements is correct?

Sleep patterns of 6 month old infants are studied.  A researcher measures the sleep time of a random sample of 6 month old infants, recording the hours of sleep over a 24 hour period.  Assume that the sleep times are normally distributed.  Find the 95% confidence interval based on the provided data.   All values are given in hours.  Round the endpoints to one decimal place.  13.3     12.8     12.6     14.3     13.3     12.6     12.8     12.2     12.7

A study is done to look at the cost of a hotel room in Paris and a hotel room in London. The sample mean cost in Paris was $534.50 per night and in London $369.50. The 95% confidence interval for cost in Paris is ($437, $632) and the 95% confidence interval for the cost in London is ($335, $404).  Which of the following statements is correct?

Suppose you want to test the claim that μ 

A college wants to determine the mean amount of credit card debt their students have.  How many students should they poll to determine the mean amount of credit card debt to within $50 at 99% confidence.  Assume that a previous study has shown that the standard deviation of the amount of credit card debt has been estimated to be $395.

A study is to be done to determine the proportion of college graduates that would choose a different major if they could go back and redo college.  What minimum sample size should be used if the researchers would like 90% confidence and a 3.6% margin of error?

For the​ following, indicate whether a confidence interval for a proportion or mean should be constructed to estimate the variable of interest. Justify your response. Researchers asked a random sample of 390 new pet owners if they would consider purchasing pet health insurance.  The confidence interval for a [prop] should be constructed because the variable of interest is [var] and this is [qual].

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, 150 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 hypothesis test is constructed so that the null and alternative hypotheses have the following meanings: Ho:  the weather stays dry (no rain) H1:  it rains You are trying to decide whether to bring your rain boots with you today in case it does rain.  Which of the following represent a Type 1 and Type 2 error in this scenario?

Sleep patterns of 6 month old infants are studied.  A researcher measures the sleep time of a random sample of 6 month old infants, recording the hours of sleep over a 24 hour period.  Assume that the sleep times are normally distributed.  Find the 95% confidence interval based on the provided data.   All values are given in hours.  Round the endpoints to one decimal place.  13.3     12.8     12.6     14.3     13.3     12.6     12.8     12.2     12.7     12.7     12.2