Scatter Plots and Line of Best Fit Review

The line of best fit for the height of a tree for various years after it was planted is

y = .96x + 8.47

Predict the height of a tree 30 years after it was planted.

• 22 feet

• 23 feet

• 36 feet

• 37 feet

Caroline weighs her new puppy every month to see how much it has grown. If age is a and weight is W, which of these is the correct equation for the line of best fit?

• W = 3.6 + 8.9

• W = 3.6a + 8.9

• a = 8.9W + 3.6

• W = 8.9a + 3.6

A data set has a line of best fit:

y = 5.57x + 25.05

("x" represents foot length and "y" represents height in cm)

If a person had a foot length of 30 cm, predict how tall they would be.

• 192 cm

• 142 cm

• 182 cm

• 162 cm

Caroline weighs her new puppy every month to see how much it has grown. If age is a and weight is W, the line of best fit would be

W = 3.6a + 8.9

Predict the age of her puppy if it weighs 20 pounds.

• 1 month old

• 2 months old

• 3 months old

• 4 months old

What type of correlation 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 140 pages. 

• 12 chapters

• 19 chapters

• 14 chapters

• 21 chapters

What is the equation of the line of best fit?

• y = -25x + 170

• y = -5/8x + 170

• y = 25x + 170

• y = 5/8x + 170

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 pages would be in a book with 6 chapters. 

• 100 pages

• 170 pages

• 60 pages

• 20 pages

You are analyzing a scatter plot that has a negative correlation. What is true of the of the x and y values?

• As x increases, y decreases

• As x increases, y increases

• As x decreases, y decreases

What is a line of best fit used for?

• To make predictions

• To make the graph look pretty

• To connect the points

• To make it look like you know what you are doing