calculate the expected number of survey respondents in each cell of the table above.  Assuming independence between the two variables, how many 18-34 year olds would we expect to prefer USPS?

The table below summarizes data from a survey of a sample of women. Using a 0.01 significance​ level, and assuming that the sample sizes of 900 men and 400 women are​ predetermined, test the claim that the proportions of​ agree/disagree responses are the same for subjects interviewed by men and the subjects interviewed by women. Does it appear that the gender of the interviewer affected the responses of​ women?                 Gender of Interviewer         Man Woman     Women who agree   625 330     Women who disagree   275 70     Compute the test​ statistic, rounding to three decimal places. Find the critical​ value(s). (Round to three decimal places) What is the conclusion based on the hypothesis​ test?

A survey was conducted to determine whether hours of sleep per night are independent of age. A sample of individuals was asked to indicate the number of hours of sleep per night with categorical options: fewer than 6 hours, 6 to 6.9 hours, 7 to 7.9 hours, and 8 hours or more. Later in the survey, the individuals were asked to indicate their age with categorical options: age 39 or younger and age 40 or older. Sample data follow. Age Group Hours of Sleep 39 or younger 40 or older Fewer than 6 38 36 6 to 6.9 60 57 7 to 7.9 76 74 8 or more 66 93 (a) Conduct a test of independence to determine whether hours of sleep are independent of age. (b) What is your estimate of the percentages of individuals who sleep fewer than 6 hours, 6 to 6.9 hours, 7 to 7.9 hours, and 8 hours or more per night?

An owner of an ice cream shop wants to investigate whether a new training program affects the scooping skills of ice cream shop employees. To assess this, the owner divides employees into two groups: those who receive training (CT) and those who do not (NT). The owner evaluates their scooping skills using a scooping proficiency test. The dataset includes the test scores of the NT (no training) group: 15.00, 7.00, 18.00, 10.00, 6.00, and 20.00, and the CT (trained) group: 15.00, 10.00, 14.00, 7.00, 21.00, and 21.00. The owner is aware of the known population mean for scooping proficiency, which is 20. The hypothesis is that employees who did not receive training (NT) will likely have lower scooping proficiency than the population mean. To investigate this hypothesis, the owner conducts a one-sample t-test with a significance level (alpha) set at 0.05. The objective is to determine if the mean scooping proficiency of the NT group is significantly different from the established population…