Question

(7 points) GPA and study time. A survey was conducted on 218 undergraduates from Duke University who took an introductory statistics course in Spring 2012. Among many other questions, this survey asked them about their GPA and the number of hours they spent studying per week. The scatterplot below displays the relationship between these two variables. 4.0 3.5 3.0 20 40 60 Study hours/week a) The explanatory variable is? b) The relationship between the variables is? c) Is this experiment or an observational study? and the response variable is ? and ? A. Observational study B. Experiment d) Can we conclude that studying longer hours leads to higher GPAs? A. Yes, we can conclude that studying longer hours leads to higher GPA since this study is an experiment. OB. Yes, we can conclude that studying longer hours leads to higher GPA since this study this is an observational study C. No. We cannot conclude that studying longer hours leads to higher GPA since this study is observational D. No. We cannot conclude that studying longer hours leads to higher GPA since this study is an experiment. E. We cannot draw any conclusion because the scatterplot has no distinct form

Answer 1

SolutionA:

explanatory variable=x=study hours per week

response variable=GPA

Solutionb:

relationship between variables is linear and strength is strong

Solutionc:

sample surveys are observational studies where researcher obseved individuals and rcor info

ANSWER:observational studies

Solutiond:'

mark option B

yes,we can conclude that studying longer hours leads to higher GPA since this study is an observational study.