The marketing department of a sports supply store wants to estimate the percentage of adults in the town who belong to a gym.
Which statement describes a method that will help the marketing department accurately estimate this percentage?
Take a random sample of adults at the local park, and ask each person whether he or she belongs to a gym. Calculate the percentage of the total who say “yes.”
Select the store’s first 20 customers every day for one week, and ask each person whether he or she belongs to a gym. Calculate the percentage of the total who say “yes.”
Take a random sample of the store’s adult customers, and ask what percentage of their friends belong to a gym. Calculate the mean of the responses.
Take a random sample of adults in the town, and ask each person whether he or she belongs to a gym. Calculate the percentage of the total who say “yes.”