The best interpretation for the y-intercept is "Students who turned in the exam at the end of the period will have an average score of 87. Hence, option D is correct.
The y-intercept of a linear graph refers to the value of the function when the x-value is 0. It is a constant value which isn't affected by the slope or the x-value.
Here, the y-intercept of the graph gives the average score for students who turned in the exam at minutes remaining = 0 , which is the end of the period.
Hence, the best interpretation is D.
Complete Question:
The scatter plot and regression line below show the relationship between how early students turned in an exam (measured by minutes remaining in the exam) and their exam scores
The fitted line has a y-intercept if 87.
What is the best interpretation of this y-intercept?