Final answer:
The sample in the high school student's survey consists of the 100 students who were surveyed, while the population is all of the students attending the high school. Representative samples are crucial for the success of a study to ensure that findings are accurately reflected across the entire population.
Step-by-step explanation:
Identifying Sample and Population
For the given situation where a high school student surveys the first 100 people entering the cafeteria on a certain day to determine satisfaction with the cafeteria food, the sample consists of the 100 students who answered the survey. The population, in this case, would be all students attending that particular high school. The student's hypothesis is that the longer a student has been at the school, the less satisfied they are with the cafeteria food.
In the given examples for the collaborative exercise, the honor students at the university would not be a representative sample for finding the average GPA of all students in a high school as they are a select and potentially higher-achieving group. The children interviewed outside the supermarket might also not form a representative sample as it does not account for those who do not shop at that supermarket or who visit at different times.
A random sample is essential for the success of a study, ensuring that each member of the population has an equal chance of being chosen, as seen in studies such as Gallup Polls or product quality checks in the manufacturing industry.