MTH 250: Chapter one examples
A report stated that "64% of people between the ages of 21 and 29 oppose farm subsidies." The percentage of 64% was computed from sample data. Complete parts (a) through (d) below. ~ a. Identify the population under consideration. ~ b. Identify the sample under consideration. The sample is all people between the ages of 21 and 29 who were surveyed. ~ c. Is the statement in quotes descriptive or inferential? Choose the correct answer below. A. The statement is descriptive, since it summarizes information about the sample. B. The statement is inferential, since it draws a conclusion about the population based on the percentage who oppose farm subsidies. C. The statement is inferential, since it draws a conclusion about the population based on a sample. Your answer is correct.D. The statement is descriptive, since it summarizes information about the population. ~ d. If you wanted to make it clear that the percentage of 64% was computed from sample data, how would you rephrase the statement in quotes? A. "64% of those surveyed between the ages of 21 and 29 oppose farm subsidies." Your answer is correct.B. "64% of all people oppose farm subsidies." C. "64% of those surveyed who oppose farm subsidies are between the ages of 21 and 29." D. "64% of those surveyed oppose farm subsidies."
All the people between the ages of 21 and 29; all the people between the ages of 21 and 29 who were surveyed;
Determine whether the study depicts an observational study or a designed experiment. A poll is conducted in which 333 elementary school students are asked about how much they read each week. Is the study an observational study or a designed experiment?
Observational
To estimate the percentage of defects in a recent manufacturing batch, a quality control manager at Toshiba selects every 17th laptop that comes off the assembly line starting with the third until she obtains a sample of 90 laptops. What type of sampling is used?
Systemic
Determine whether the study depicts an observational study or an experiment. Ninth dash grade students are randomly divided into two groups. One group is taught English using traditional techniques. The other is taught English using a reform method. After 1 year comma each group is given an achievement test to compare its proficiency with that of the other group. Choose the correct description of the study
The study is a designed experiment
Determine whether the study depicts an observational study or an experiment. Eighty patients with stomach cancer are divided into two groups. One group receives an experimental drug to fight cancer comma the other a placebo. After one year comma the spread of the cancer is measured. Does the description correspond to an observational study or an experiment?
The study is experimental; designed experiment