Bivariate Data Analysis and Mad

What is the equation of the line of best fit?

• y= 2x+3

• y=3x+2

What is the equation of the trend line?

A city manager made a scatter plot of the number of retail stores in the city over the years. A scatter plot had a trend line with an equation of y=11x+12, where y is the total number of retail stores and x is the number of years since 1990. Use the equation to predict the number of retail stores in the city in 1997. (7 years later).

• 89

• 77

• 7

• 98

A scatter plot was created to show the length of a person's vacation and the weight of the suitcase they packed. The equation of the trend line is y=5x+15, where x represents the length of the trip.

Use the equation to predict the weight of a suitcase for someone taking a 9-day trip.

• 45

• 60

• 15

• 55

In a scatterplot, an outlier...

• ...is something we didn't learn in 8th grade

• ...is a point on the origin

• ...is a point that is far outside the main cluster of points/ordered pairs

• ...is a group of points that are close together

A line drawn on a scatter plot that is close to most of the data points.

• Best fitting line

• Best Linear Line

• Line of best fit

Write the equation that best matches the graph shown.

• y = 4x

• y = 4x - 3

• y = 4/3 x + 4

• y = 4/3 x - 3

Several schools reported the number of students who received a flu vaccine in a year and the number of cases of the flu amongst their students that year. A scatter plot was made with a trend line that had an equation of y=-\frac{1}{4}x+85. Use the equation to predict the number of cases of the flu that would occur if 300 students received he flu vaccine.

• 75

• 160

• 300

• 10

What type of association does this graph have?

• positive 

• negative

• none

• all of the above

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. (Where does the line match up with the x value of chapters?)

• 12 chapters

• 15 chapters

• 18 chapters

• 21 chapters