Have you ever noticed that adults like the taste of some bitter foods that adolescents just cannot tolerate the taste of? Things like dark chocolate, grapefruit, coffee, etc. Ms. Wilson is interested in whether bitter flavors become more tolerable as people get older. She sets up a study in which subjects taste cups of coffee that are different strengths and picks their favorite one. Ms. Wilson records the age of each subject, x, and the strength of the coffee in grams, y, that the subject liked the best. Age of Subject Strength of Coffee in grams 17 48 27 44 33 49 37 54 40 57 r = y = x + If someone was 45 years old, what would the regression line predict for the strength of coffee they would prefer?
The regression line equation is:
y = 0.92x + 13.55
To find the predicted strength of coffee for a 45-year-old subject, we substitute x = 45 into the equation:
y = 0.92(45) + 13.55
y = 41.4 + 13.55
y = 54.95
Therefore, the regression line predicts that a 45-year-old subject would prefer a strength of approximately 55 grams of coffee.