Question:

A seventh grade class of twenty-seven students wants to estimate the proportion of eligible voters in their school district who intend to vote in the upcoming school board election. They decide to base their estimate on 270 eligible voters. Which of the following plans would allow the class to generalize from the sample to the population of all eligible voters?

(A) Have each of the 27 students randomly select 10 neighbors to participate in the survey.
(B) Mail surveys to all eligible voters and take the first 270 who respond.
(C) Mail surveys to 270 randomly selected eligible voters and follow-up with those who do not respond.
(D) Survey 270 people visiting a local grocery store on the Saturday before the election.

Level:
Intermediate

Standards

7.SP.1: Understand that statistics can be used to gain information about a population by examining a sample of the population; generalizations about a population from a sample are valid only if the sample is representative of that population. Understand that random sampling tends to produce representative samples and support valid inferences.

S-IC.3: Recognize the purposes of and di"erences among sample surveys, experiments, and observational studies; explain how randomization relates to each.