Question

Jordan plotted the graph below to show the relationship between the temperature of his city and the number of cups of hot chocolate he sold daily:A scatter plot is shown with the title Jordans Hot Chocolate Sales. The x axis is labeled High Temperature and the y axis is labeled Cups of Hot Chocolate Sold. Data points are located at 20 and 20, 30 and 18, 40 and 20, 35 and 15, 50 and 20, 45 and 20, 60 and 14, 65 and 18, 80 and 10, 70 and 8, 40 and 2.Part A: In your own words, describe the relationship between the temperature of the city and the number of cups of hot chocolate 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)

Answer 1

A.

Overall it has a relation that there are more sold cups when the temperature is lower. On the other hand, based on the 40 degrees part, that have to different values of two different days, we can say is not the only factor.

B.

The best lineal approach is the line created with the points at 20 and 80 degrees. First the slope:

`m=(y1-y2)/(x1-x2)=(20-10)/(20-80)=(10)/(-60)=-(1)/(6)`

Now the intercept with y axis, b:

`\begin{gathered} y=mx+b \\ 20=20(-(1)/(6))+b \\ 20+(20)/(6)=b=23.33=(70)/(3) \end{gathered}`

The final line formula is:

`y=-(x)/(6)+(70)/(3)`