Answer
Parents take their children to the movies to watch a children's movie. After the end of the movie, a survey is conducted to determine whether the audience liked or not. Three different questionnaires are prepared for three diffrent groups: children under 14 years old, adolescents of 14 to 21 years of age, and adults that are over 22 years old. A simple random sample is obtained from each group (strata).
Work Step by Step
The individuals of each group are homogeneous: it is expected that they have a similar opinion about the movie. So, a smaller number of respondents is required.
