Question

Sally reads a report about a casual study of students and their attitudes to drugs. "a group of high school students were asked if they had ever used an illegal substance; the majority of those students said 'no.'" sally then cites this study in her paper about drug use. she says, "a study of students revealed that only 10% of high school students use drugs." why is her conclusion flawed

Answer 1

the report didn't give any numbers. She came up with the figure "10%" on her own. "most" does not necessarily mean "90%".

Answer 2

In this example, the report that Sally read divided high school students in two groups: those that had ever used an illegal substance and those who had not. The study states that the majority of students said that they had never used illegal substances. However, we only know that most students had not used illegal drugs, but we do not know that the proportion was 90-10. The numbers, therefore, are deceptive, which means that Sally's conclusion is flawed.