A researcher studying public opinion of proposed Social Security changes obtains a simple random sample of 25 adult Americans and asks them whether or not they support the proposed changes. To say that the distribution of the sample proportion of adults who respond​ yes, is approximately​ normal, how many more adult Americans does the researcher need to sample in the following​ cases?   ​(a) 20​% of all adult Americans support the changes ​(b) 25​% of all adult Americans support the changes ​(a) The researcher must ask _____more American adults. ​(Round up to the nearest​ integer.)

A researcher studying public opinion of proposed Social Security changes obtains a simple random sample of 25 adult Americans and asks them whether or not support the proposed changes . To say that the distribution of the sample proportion of adults who respond yes, is approximately normal , how many more adult Americans does the researcher need to sample in the following cases? (a) 15% of all adult Americans support the changes (b) 20% of all adult Americans support the changes

A researcher studying public opinion of proposed Social Security changes obtains a simple random sample of 50 adult Americans and asks them whether or not they support the proposed changes. To say that the distribution of the sample proportion of adults who respond yes, is approximately normal, how many more adult Americans does the researcher need to sample in the following cases? (a) 15% of all adult Americans support the changes (b) 20% of all adult Americans support the changes (a) The researcher must ask more American adults. (Round up to the nearest integer.) (b) The researcher must ask more American adults. (Round up to the nearest integer.)

Random digit dialing telephone surveys used to exclude cell phone numbers. If the opinions of people who have only cell phones differ from those of people who have landline service, the poll results may not represent the entire adult population. The Pew Research Center interviewed separate random samples of cell-only and landline telephone users who were less than 30 years old. Here’s what the Pew survey found about how these people describe their political party affiliation.     Do we reject, or fail to reject, the null hypothesis?

Sierra College students enrolled in an online Elementary Statistics course were asked to participate in an anonymous onlne survey. The survey asked the students "Which type of device will you primarily use to access your online course in Canvas?". Of the 152 students who answered this question, 20 responded "a desktop computer", 121 responded "a laptop computer", 6 responded "a smartphone", and 5 responded "a tablet". The Sierra College Mathematics Department believes that less than 5% of students enrolled in an online Elementary Statistics course primarily uses a smartphone to access their online course in Canvas. Use the data collected in the survey to conduct a hypothesis testing procedure to test this belief. What conclusion should be reached according to the results of this hypothesis test?

(6) A student surveys some students on campus in the evening and finds that 16 out of 20 of the students she interviewed are part time students. She uses the data to estimate the percentage of all students who are part time. What type of bias is present in her sample?