Question

5 a student is curious about the average age of a nickel in circulation. the student collects nickels for a few months and places them in a jar. once the jar is full, the student mixes up the nickels, randomly selects 100 of them, records the age of each penny selected, and finds the average age. which of the following best describes the way the average age of a nickel in circulation was determined? a a sample survey b an observational study c an experiment that used a control group d an experiment that did not use randomization

Explanation:

A sample survey involves collecting data from a subset (sample) of a population to estimate a population characteristic. Here, the student randomly selects 100 nickels (sample) from the jar of collected nickels (population proxy for circulating nickels) to find the average age, which matches a sample survey. An observational study observes without intervention but does not focus on sampling for estimation; experiments involve manipulating variables, which is not done here.

Answer:

A. a sample survey