Lesson 19
fitting a line to data
Unit 5
linear relationships
SLIDESMANIA.COM
19.1: Predict This
If a car weighs 1,750 kg, would you expect its fuel efficiency to be closer to 22 mpg or to 28 mpg? Explain your reasoning.
SLIDESMANIA.COM
Learning Targets
Success criteria
SLIDESMANIA.COM
19.2: Shine Bright
Here is a table that shows weights and prices of 20 different diamonds.
SLIDESMANIA.COM
19.2: shine Bright
1. Two diamonds that both weigh 1.5 carats have different prices. What are their prices? How can you see this in the table? How can you see this in the graph?
2. The model predicts that when the weight is 1.5 carats, the price will be $7,189. How can you see this in the graph? How can you see this using the equation?
SLIDESMANIA.COM
19.2: shine Bright
3. One of the diamonds weighs 1.9 carats. What does the model predict for its price? How does that compare to the actual price?
4. Find a diamond for which the model makes a very good prediction of the actual price. How can you see this in the table? In the graph?
5. Find a diamond for which the model’s prediction is not very close to the actual price. How can you see this in the table? In the graph?
SLIDESMANIA.COM
19.3: The Agony of the Feet
Here is a scatter plot that shows lengths and widths of 20 different left feet.
1. Estimate the widths of the longest foot and the shortest foot.
2. Estimate the lengths of the widest foot and the narrowest foot.
SLIDESMANIA.COM
19.3: The Agony of the Feet
3. Here is the same scatter plot together with the graph of a model for the relationship between foot length and width.
Circle the data point that seems weird when compared to the model. What length and width does that point represent?
SLIDESMANIA.COM
Lesson Summary
SLIDESMANIA.COM
Cool Down: A 1 Foot Foot
Here is a scatter plot that shows lengths and widths of 20 left feet, together with the graph of a model of the relationship between foot length and width.
1. Draw a box around the point that represents the foot with length closest to 29 cm.
2. What is the approximate width of this foot?
3. What width does the model predict for a foot with length 29 cm?
SLIDESMANIA.COM
Reflections
• Can you describe the meaning of a point in a scatterplot in context?
SLIDESMANIA.COM
Practice Problems
SLIDESMANIA.COM
Lesson Video
SLIDESMANIA.COM