Scatterplots Correlation Line of Best Fit

Which data will most likely show a negative correlation when graphed on a scatter plot?

• The outside temperature and the number of people wearing gloves.

• The distance a student lives from school and the amount of time it takes to get to school.

• The number of visitors at an amusement part and the length of the lines for the rides.

• A student's height and grade point average.

What is the best prediction for the number of candies in the jar when 30 students visit her?

• 90

• 180

• 135

• 150

Find the slope from the table:

• -2/5

• 5/-2

• 5/2

• 2/5

What type of correlation would you likely see with:

The amount of time spent working compared to the amount of money earned

• positive correlation

• negative correlation

• no correlation

Which of the following could be a possible line of best fit for the data?

• y = -5/2x + 20

• y = -x + 19

• y = x + 20

• y = 2/3x + 15

Estimate the correlation coefficient

• r = 1

• r = -1

• r ≈ -0.8

• r ≈ 0.8

• r ≈ -0.5

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 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

Suppose data related to the AVERAGE Temperature outside (T) and the number of winter Coats (C) sold at a store is collected and graphed. The LINE OF BEST FIT has the equation C = -3T + 150. Use this equation to predict the number of coats sold when the average temperature outside is 20°.

• 40

• 75

• 90

• 115

A researcher gathered data to predict the number of new types of plants (y) that will be in a state park after x years.  After making a scatter plot of the data, she determined the equation of a line of best fit to be
y = 0.25x + 8
Based on the equation, what is the number of new types of plants that will be in the park after 24 years?

• 8

• 14

• 32

• 64