Scatter Plots, Line of Best Fit, Equations

Hubert has a record of his heights from first grade through seventh grade. He constructed a scatter plot and line of best fit to show his height at each grade level. Which equation is most likely to represent the line of best fit?

• y = ¹/₄₁ x + ¹/₃

• y = 41x + 3

• y = ¹/₃ x + 41

• y = 3x + 41

The graph below shows the value of a computer given the age of the computer. Which equation would best fit the data?

• y = -250x + 2000

• y = 250x + 2000

• y = -250x - 2000

• y = 2000x -250

The table shows the age and value of a vehicle over several years. Which equation would best fit the data?

• y = –1,500x + 20,000

• y = 1,500x + 20,000

• y = ^–2,000x + 22,000

• y = 2,000x + 22,200

Mr. Larson recorded the heights and arm spans of the students in his science class. The results are shown on the scatterplot. Using the scatterplot, which best predicts the arm span of a student who is 57 inches tall?

• 58 inches

• 57 inches

• 55 inches

• not enough information is given

The scatter plot shows the amount of time played and the number of points scored by ten basketball players during their last four games. Which conclusion best describes the data?

• The players who scored the most points played the longest

• There is no correlation between the time played and the number of points scored

• There is a positive correlation between time played and the number of points scored

• There is a negative correlation between time played and the number of points scored

A used-car dealer kept records of the selling price of his used cars in 2005. The scatter plot shows the average selling price of his used cars based on the age of the used car. Using the graph, which is the closest to the selling price of an 8-year-old car?

• $7,500

• $5,000

• $2,500

• $500

Which is the best description of the data shown on this graph?

• nonlinear with a negative trend

• nonlinear with a positive trend

• linear with a negative trend

• linear with a positive trend

The graph shows the number of umbrellas sold at a certain store relative to the amount of rainfall in the town per month. Based on the line of best fit, approximately how many umbrellas would be sold if there were 6 inches of rain?

• 20

• 35

• 40

• 45

The scatter plot below shows John’s scores in the seven math and science chapter tests this semester. Which statement best describes the association between his math and science test scores?

• There is a positive linear association between the math and science scores.

• There is a negative linear association between the math and science scores

• There is a positive linear association between the math and science scores and 1 outlier

• There is a negative linear association between the math and science scores and 1 outlier.

The scatter plot shows the number of hours Mr. Liu’s students spent watching TV compared to the hours they spent playing computer games during a week. Which best describes the association between the two quantities?

• weak positive correlation

• weak negative correlation

• strong positive correlation

• strong negative correlation