Question

Liz's math test included a survey question asking how many hours students spent studying for the test. The scatterplot and regression line below show the relationship between how many hours students spent studying and their score on the test. The fitted line has a slope of 15. What is the best interpretation of this slope?

A) The model predicts that students who scored 0 studied for an average of 15 hours.

B) The model predicts that students who didn't study at all will have an average score of 15 points.

C) The model predicts that the score will increase by 15 points for each additional hour of study time.

D) The model predicts that the study time will increase by 15 hours for each additional point scored.

Answer 1

The slope of 15 in the regression line predicts that for each additional hour of study time, the average test score will increase by 15 points.

Step-by-step explanation:

The best interpretation of the slope in a regression line, which in this case is 15, is that the model predicts that for each additional hour spent studying, the score on the test is expected to increase by 15 points, on average. Therefore, the correct answer to the question is (C) The model predicts that the score will increase by 15 points for each additional hour of study time. This understanding is based on how the slope indicates the change in the dependent variable (in this case, the test score) for each one-unit increase in the independent variable (the study hours).