Question 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 (4 points) Use the Desmos Graphing Calculator (right-click and open in new tab/window) to calculate the following: r = y = x + If someone was 45 years old, what would the regression line predict for the strength of coffee they would prefer?

1 answer

To analyze the relationship between age and the strength of coffee preferred, we first need to find the equation of the regression line based on the data provided. The regression line can be expressed in the form:

\[ y = mx + b \]

where:

  • \( y \) is the strength of coffee in grams,
  • \( x \) is the age of the subject,
  • \( m \) is the slope of the regression line,
  • \( b \) is the y-intercept.

Let's assume you've already entered the data into Desmos or a statistical calculator to obtain the correlation coefficient \( r \) and the regression equation.

Given the ages and corresponding coffee strengths:

  • \( (17, 48) \)
  • \( (27, 44) \)
  • \( (33, 49) \)
  • \( (37, 54) \)
  • \( (40, 57) \)

After calculating the regression line, use the equation to find the predicted strength of coffee for someone who is 45 years old by substituting \( x = 45 \) into the regression equation.

If you have the values of \( m \) and \( b \) from your regression analysis, you can calculate it as follows:

Let's assume the regression equation derived from your calculations is in this form (for example):

\[ y = mx + b \]

Then you just substitute:

  1. Substitute \( x = 45 \): \[ y = m(45) + b \]

This will give you the predicted coffee strength for a 45-year-old.

Since I do not have access to the Desmos Graphing Calculator, please carry out these calculations in the tool or provide the regression equation, and I can help you with further analysis!