Scatter Plots and Line of Best Fit

Multiple Choice

Check for understanding:What type of correlation does this graph have?

• positive
• negative
• none
• all of the above

Multiple Choice

Check for understanding: Which correlation coefficient best describes the correlation shown?

• 0

• -0.75

• -0.3

• 0.3

Multiple Choice

Check for understanding: What correlation coefficient would be describe the correlation?

• 0

• -0.999

• 0.978

• 0.2

Multiple Choice

Check for understanding: What does the correlation coefficient for the data indicate about the strength of the linear association between the x and y variables

Hint: what is the correlation based on the scatter plot

• strong negative

• weak negative

• strong positive

• weak positive

Multiple Choice

Check for understanding: Which statement best explains whether the trend line is a good fit for the data

• It is not a good fit because there is an outlier.

• It is not a good fit because the majority of data points are below the line

• It is a good fit because it passes through at least one data point.

• It is a good fit because the data goes up and so does the trend line.

Multiple Choice

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

• A
• B
• C
• D

Multiple Choice

Check for understanding: Write an equation of the trend line in slope-intercept form.

• $$y\ =\ 2x-155$$

• $$y=25x+150$$

• $$y=\ 150x+200$$

• $$y=30x+150$$

Multiple Choice

Check for understanding: Which of the following could be a possible line of best fit for the data?

• y = -5/2x + 20
• y = -x + 19
• y = x + 20
• y = 2/3x + 15 

Multiple Choice

Check for understanding: Which equation represents a line of best fit for this graph?

• y= x
• y= 2x
• y= -x - 2
• y= 2x + 2

Multiple Choice

Check for understanding

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

Multiple Choice

Check for understanding: The scatterplot shows the relationship between the length of a long-distance phone call and the cost of the phone call.

Based on the line of best fit for the scatterplot, which of the following amounts is closest to the cost of a 120 minute phone call?

• $10

• $12

• $15

• $20

Open Ended

Check for understanding: Find the trend line that best represent this scatter plot. What would the expected sales be if the cost were set at $6.50? Explain what that means in the context of the data