In the city of Santa Maria, the coffee shops have been keeping track of their sales during the year. They noticed a relationship between the amount of hot coffee sold and the temperature. The data was organized in the table below.

\begin{tabular}{|c|c|}
\hline
Temp [tex]$\left({ }^{\circ} F \right)$[/tex] & Coffee Sales (thousands of dollars) \\
\hline
55 & 34 \\
58 & 33 \\
66 & 27 \\
70 & 25 \\
75 & 22 \\
80 & 17 \\
85 & 12 \\
\hline
\end{tabular}

According to your equation, what are the coffee sales when the temperature is 40°F?



Answer :

To determine the coffee sales when the temperature is 40°F, we'll analyze the correlation between temperature and sales using a linear model based on the provided data. We can summarize the steps to build our model and predict the sales as follows:

1. Data Collection: We have the temperature and coffee sales data collected as follows:
- 55°F: [tex]$34,000 - 58°F: $[/tex]33,000
- 66°F: [tex]$27,000 - 70°F: $[/tex]25,000
- 75°F: [tex]$22,000 - 80°F: $[/tex]17,000
- 85°F: [tex]$12,000 2. Model Construction: By fitting a linear model to this data, we obtain a linear equation that represents the relationship between temperature (T) and sales (S). The general form of the linear equation is: \[ S(T) = a \cdot T + b \] Here, \(a\) and \(b\) are the coefficients of the line, which were determined to be approximately \(a = -0.7208\) and \(b = 74.6415\). 3. Predicting Sales: Using this linear equation, we can predict the coffee sales at a given temperature. We plug in the temperature of interest (in this case, 40°F) into the equation. \[ S(40) = -0.7208 \cdot 40 + 74.6415 \] 4. Calculation: \[ S(40) = -28.832 + 74.6415 = 45.8095 \] Thus, when the temperature is 40°F, the expected coffee sales are approximately \(45,809.5\) dollars. So, according to our model, the coffee sales when the temperature is 40°F would be about $[/tex]45,809.50.