The problem states that in a large random sample of American students in seventh grade, 20% of them were reading below grade level. The question asks to choose the valid conclusion based on this data.
2025/3/8
1. Problem Description
The problem states that in a large random sample of American students in seventh grade, 20% of them were reading below grade level. The question asks to choose the valid conclusion based on this data.
2. Solution Steps
Option A states: "About 20% of all American students in seventh grade were reading below grade level." Since the sample is random and large, we can infer that the percentage of students reading below grade level in the population is approximately the same as in the sample. So, this conclusion is plausible.
Option B states: "20% of this sample was reading below grade level, but we cannot conclude anything about the population." This statement is incorrect. Since the sample is large and random, we can make inferences about the population.
Option C states: "About 20% of all American students were reading below grade level." This statement is too broad since it doesn't specify which grade level it is referring to. The information we have is only for seventh-grade students.
Therefore, Option A is the most accurate and valid conclusion.
3. Final Answer
About 20% of all American students in seventh grade were reading below grade level.