Naomi plotted the graph below to show the relationship between the temperature of her city and the number of popsicles she sold daily:
A scatter plot is shown with the title Naomis Popsicle Stand. The x axis is labeled High Temperature, and the y-axis is labeled Number of Popsicles Sold. Data points are located at 90 and 20, 85 and 17, 70 and 14, 75 and 20, 60 and 16, 50 and 14, 60 and 12, 40 and 10, 50 and 12, 80 and 8.
Part A: In your own words, describe the relationship between the temperature of the city and the number of popsicles sold. (2 points)
Part B: Describe how you can make the line of best fit. Write the approximate slope and y-intercept of the line of best fit. Show your work, including the points that you use to calculate the slope and y-intercept. (3 points)
Part A: The relationship between the temperature of the city and the number of popsicles sold appears to be negative. As the temperature increases, the number of popsicles sold decreases.
Part B: To find the line of best fit, we can calculate the slope and y-intercept using two points from the data. Let's use the points (90, 20) and (40, 10):
Slope = (10 - 20) / (40 - 90) = -10 / -50 = 0.2
Now, we can use the slope and one of the points to find the y-intercept:
y = mx + b
10 = 0.2(40) + b
10 = 8 + b
b = 2
Therefore, the line of best fit can be represented by the equation y = 0.2x + 2.