Question

Nan investigated how many students at her high school had summer jobs. Which of the following is the procedure of her investigation?
A. If about 75 percent of all students at Central High have summer jobs, then about 1200 students have summer jobs.
B. First, randomly select 100 students, then ask them if they have summer jobs.
C. Of the 100 students selected for the survey, 61 answered that they do have summer jobs, and 39 answered that they do not.
D. About 61 percent, or 983, of the students at Central High have summer jobs.

Answer 1

In order to answer her question regarding how many students at her high school had summer jobs Nan must follow the procedure given in answer option B: First, randomly select 100 students, then ask them if they have summer jobs. In statistics this method is known as Population Sampling. These 100 students are chosen at random in order to avoid bias - we need them to be representative of the entire high school population.