Question

Data was collected on the amount of time that a random sample of 8 students spent studying for a test and the grades they earned on the test. A scatter plot and line of fit were created for the data.

scatter plot titled students' data, with points plotted at 1 comma 60, 2 comma 60, 2 comma 70, 2 comma 80, 3 comma 80, 3 comma 90, 4 comma 95, and 4 comma 100, and a line of fit drawn passing through the points 0 comma 40 and 2 comma 70

Find the slope of the line of fit and explain its meaning in the context of the data.

Answer 1

2 hours: 70 on test, 3 hours: 100 on test.

Explanation:

The line of fit shows that for every hour that a student studies, their grade on the test is expected to increase by 30 points. This means that there is a positive correlation between the amount of time that a student studies and their grade on the test. In other words, students who study for longer tend to get higher grades on the test.

For example, if a student studies for 2 hours, they can expect to get a grade of 70 on the test. If they study for 3 hours, they can expect to get a grade of 100 on the test.

Of course, this is just an estimate based on the data from the 8 students in the sample. It is possible that the slope of the line would be different if the sample included more students. However, the slope of the line is still a good estimate of the relationship between the amount of time that a student studies and their grade on the test.