As part of a statistics project, a 6th grade teacher brings to class a container with 300 red marbles and 500 white marbles which are thoroughly mixed. To figure out how many marbles in the container are red without actually counting them all, a student randomly draws 40 marbles from the container. Of the 40 marbles drawn, 16 are red.
The data collection method can best be described as
◦ a controlled study.
◦ a survey.
◦ a census.
◦ a clinical study.
◦ none of these