Scatter Plots

What is an equation for the line of best fit?

• y = 20/3 x + 40

• y = -20/3 x + 40

• y = -20/3 x - 40

• y = 20/3 x - 40

Predict the number of cases of the flu that would occur if 300 students received a flu vaccine.

• 1115

• 860

• 1285

• 10

Predict how many students received a flu vaccine if a school had 65 cases of the flu.

• 105

• 80

• -80

• 37.5

What is the Y-INTERCEPT of the trend line equation, and what does it mean in the context of the situation?

• The y-intercept is the number of cases of the flu in total.

• The y-intercept is the number of cases of the flu with 0 vaccines given.

• The y-intercept is the number of vaccines when there are 0 cases of the flu.

• Hint: Remember that y-intercept is the value of y when x is 0. Read what represents x and what represents y. DON'T PICK THIS ANSWER....IT IS JUST A CLUE.

Is this scatter plot linear or non-linear?

• Linear

• Non-Linear

The scatter plot shows the relationship between the number of chapters and the total number of pages for several books.  Use the trend line to predict how many chapters would be in a book with 180 pages. 

• 12 chapters

• 15 chapters

• 18 chapters

• 21 chapters

Which scatter plot show a positive relationship?

• Graph A

• Graph B

• Graph C

• Graph D

Which scatter plot shows a negative relationship?

• Graph A

• Graph B

• Graph C

• Graph D

• y = x ; 20
• y = x + 2 ; 22
• y = 2 ; 2
• y = 0.5x + 2 ; 12

Which of the following lines represents the line of best fit for the scatter plot?

• A

• B

• C

• D