Making Predictions with Line of Best Fit

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

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

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 19 chapters. 

• 150 pages

• 170 pages

• 190 pages

• 210 pages

The red line represents the line of best fit for the scatter plot. How many ice cream sales are expected if the temperature is 90°?

• 55

• 0

• 103

• 100

The scatter plot shows the amount of sleep Aria got the night before a test and her test scores. Which is the best prediction for Aria’s grade when she sleeps for 10 hours?

• 75

• 83

• 92

• 99

Tags

CCSS.8.F.B.4

CCSS.HSF.LE.A.2

• y = 1.45x + 22
• y = -2x + 15
• y = 1.33x + 30
• y = -1.5x + 24

Using your line of best fit equation from the last question, what is y when x is 30?

• 61.59

• 52.46

• 57.94

• 59.76

Tags

CCSS.HSF-LE.A.1B

The scatter plot shows the relationship between the number of chapters and the total number of pages for several books. Use the line of best fit 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= 6x + 2

• y = -2x +6

Tags

CCSS.8.EE.B.5