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.
(less than 300 characters)
Part A: The relationship between the temperature of the city and the number of popsicles sold seems to be negative. As the temperature increases, the number of popsicles sold decreases.
Part B: To make the line of best fit, I would calculate the slope using two points, for example (90, 20) and (40, 10). The slope is (20-10)/(90-40) = 10/50 = 0.2. To find the y-intercept, I can use point (90, 20) and substitute the slope in the equation y = mx + b, where y = 20, x = 90, and m = 0.2. Solving for b, I get b = 20 - 0.2*90 = 2. Therefore, the line of best fit equation is y = 0.2x + 2.