### Home > CCAA8 > Chapter 7 Unit 8 > Lesson CCA: 7.1.1 > Problem7-11

7-11.

Data for a study of a vitamin supplement that claims to shorten the length of the common cold is shown below:

 Number of months taking supplement Number of days cold lasted $0.5$ $2.5$ $1$ $2$ $0.5$ $1$ $2$ $1$ $1.5$ $2.5$ $4.5$ $1.6$ $3$ $1.8$ $5$ $4.2$ $2.4$ $3.6$ $3.3$ $1.4$
1. You previously created linear models for this data in problems 6-24 and 6-55. Sketch the graph and the LSRL

Look at the Math Notes box in Lesson 6.2.1 to help you with LSRL graphs..

2. Is a linear model appropriate? Provide evidence.

Yes. Make sure you provide evidence for why.

3. Find r and interpret R-squared in context.

Look at the Math Notes box in Lesson 6.2.4 to refresh your memory about these values.

4. Describe the association. Make sure you describe the form and provide evidence for the form. Provide numerical values for direction and strength and interpret them in context. Describe any outliers.

Form: Is the association linear or nonlinear?
Direction: Positive or negative?