In 2017, 20.1% of all high school students in the U.S. had a job. A school official from a district thought that the percentage of high school students who had a job in that school district was higher than the national proportion. She took a random sample of 285 high school students and found that 64 of had a job.Is this survey valid or not valid for testing the hypothesis that the proportion of the high school students who worked in that district is higher than the national average?

Dr. Gray would like to do a survey on whether the proportion of people ages 18 to 22 who have seen a healthcare professional (doctor, nurse, hospital, etc.) in the past year is higher than the national average of 82%. She plans to give her survey to 80 student athletes at your college by distributing surveys after sports practice. Is this survey valid or not valid for testing the hypothesis that the proportion of people ages 18 to 22 who have seen a healthcare professional in the past year is higher than the national average? Valid Not valid

A university newspaper claims that 46% of college students at that university have a job outside of the university. A statistics professor thinks that the actual number is less than this. She asks her students to conduct a survey with a random sample of 200 students. According to their results, 82 of the surveyed students have a job outside of the university. They calculated the test statistics: z = -1.42.Using 5% significance level, do they have enough evidence to reject the newspapers claim?

A researcher would like to estimate p, the proportion of U.S. adults who support raising the federal minimum wage.Due to a limited budget, the researcher obtained opinions from a random sample of only 1,432 U.S. adults. With this sample size, the researcher can be 95% confident that the obtained sample proportion will differ from the true proportion (p) by no more than which of the following percentages (answers are rounded)? 0.07% 2.6% 3.0% 5.2%

A manager of a company believes that the average age of its customers is 40. However, theCEO of the company thinks that the average age of the company’s customers differs from 40. To testthis, she randomly selected 60 customers, and the average customer age was found to be 42.7 years.Assume the (population) standard deviation for customer age is 8 years. Using a 5% level ofsignificance, does the sample provide enough evidence to refute the claim made by the manager

Caden surveyed 7 teachers from each academic department at school. Each department has an equal number of teachers.Is this sample of the teachers in the school likely to be biased?yesnoSubmit