Scatterplot Linear Regression

The table shown is comparing a person's foot length to their height in cm. Calculate a line of best fit.

• f(x) = 25.05x + 5.57

• f(x) = 5.57x + 25.05

• f(x) = -5.57x + 25.05

• f(x) = 5.57x - 25.05

Shelia collected data on ticket sales for the homecoming dance.  If she plots the data on the scatterplot shown above, which equation best models the table?

• y = 4.22x + 20.98

• y = 4.22x - 20.98

• y = -4.22x + 20.98

• y = -4.22x - 20.98

Make a prediction for a resting heart rate after 6 hours of exercise a week.

• 6

• 50

• 55

• 59

Phil collected data from several of his friends about the number of hours they spent sleeping and the number of hours they spent playing video games on Saturday. He recorded the data in the scatterplot. Based on the scatterplot, what is the best prediction of the number of hours one of Phil's friends spends sleeping when the friend spends 1 hour playing video games?

• 9 hours

• 10 hours

• 7 hours

• 8 hours

Students in a science class investigated how the speed of changes with the air temperature outside. The data is shown in the scatterplot. Based on the scatterplot, what is the best prediction of the speed of sound when the air temperate is 50 degrees C?

• 350 m/s

• 355 m/s

• 360 m/s

• 380 m/s

The scatterplot shows the number of people in each of 8 different households and the average amount of money each household spent on groceries. Based on the scatterplot, what is the best prediction of the average amount of money spent on groceries for a household that has 7 people?

• $240

• $190

• $210

• $300

The scatterplot shows the average number of hours each of 13 people spends at work every week and the average number of hours each of them spends on recreational activities every week. Based on the scatterplot, what is the best prediction of the average number of hours a person spends at work every week if that person spends an average of 10 hours on recreational activities each week?

• 33 h

• 85 h

• 50 h

• 65 h

About how many male math teachers were there in 2006?

• 15

• 30

• 35

• 45

Estimate the correlation coefficient for this scatterplot.

• r = 1.2

• r = 0.89

• r = 0

• r = -0.89

Describe the relationship between the variables.

• A) Weak positive correlation

• B) Weak negative correlation

• C) Strong positive correlation

• D) Strong negative correlation