Final answer:
To achieve a score of 100 on the exam based on the given regression line with a slope of 4 and a y-intercept of 20, a student would need to study for 20 hours.
Step-by-step explanation:
The question requires us to find the expected study time for a student who wants to score 100 on an exam based on a given regression line equation. The regression line equation provided is y = 4x + 20, where 'y' is the score on the exam, and 'x' is the number of hours spent studying. To find the expected study time for a score of 100, we set y = 100 and solve for x.
100 = 4x + 20
Subtract 20 from both sides to isolate the term with x:
80 = 4x
Divide both sides by 4 to solve for x:
20 = x
Therefore, a student should expect to study for 20 hours to achieve a score of 100 on the exam, based on the regression line provided.