College

The function [tex]f(t)=349.2(0.98)^t[/tex] models the relationship between [tex]t[/tex], the time an oven spends cooling, and the temperature of the oven.

Oven Cooling Time

[tex]\[

\begin{tabular}{|c|c|}

\hline

\begin{tabular}{c}

Time \\

(minutes) \\

$t$

\end{tabular} & \begin{tabular}{c}

Oven temperature \\

(degrees Fahrenheit) \\

$f(t)$

\end{tabular} \\

\hline

5 & 315 \\

\hline

10 & 285 \\

\hline

15 & 260 \\

\hline

20 & 235 \\

\hline

25 & 210 \\

\hline

\end{tabular}

\][/tex]

For which temperature will the model most accurately predict the time spent cooling?

A. 0

B. 100

C. 300

D. 400

Answer :

To solve this problem, we want to determine which temperature the model most accurately predicts the time spent cooling. The model is expressed by the function [tex]\( f(t) = 349.2 \times (0.98)^t \)[/tex], which gives the temperature of the oven, [tex]\( f(t) \)[/tex], at a given time [tex]\( t \)[/tex] in minutes.

Here’s the step-by-step solution:

1. Understand the problem: We need to compare the model's predictions with the actual temperatures given in the provided data at specific times.

2. Review the provided table: The table lists times in minutes (5, 10, 15, 20, and 25) and their corresponding actual recorded temperatures (315°F, 285°F, 260°F, 235°F, and 210°F).

3. Use the model to predict temperatures: Apply the function for each of the given time samples to predict the temperatures:
- At [tex]\( t = 5 \)[/tex]: [tex]\( f(5) = 349.2 \times (0.98)^5 \)[/tex]
- At [tex]\( t = 10 \)[/tex]: [tex]\( f(10) = 349.2 \times (0.98)^{10} \)[/tex]
- At [tex]\( t = 15 \)[/tex]: [tex]\( f(15) = 349.2 \times (0.98)^{15} \)[/tex]
- At [tex]\( t = 20 \)[/tex]: [tex]\( f(20) = 349.2 \times (0.98)^{20} \)[/tex]
- At [tex]\( t = 25 \)[/tex]: [tex]\( f(25) = 349.2 \times (0.98)^{25} \)[/tex]

The predictions from these calculations are:
- [tex]\( f(5) \approx 315.65 \)[/tex]
- [tex]\( f(10) \approx 285.32 \)[/tex]
- [tex]\( f(15) \approx 257.91 \)[/tex]
- [tex]\( f(20) \approx 233.13 \)[/tex]
- [tex]\( f(25) \approx 210.73 \)[/tex]

4. Calculate the differences: For each time point, find the absolute difference between the predicted temperature and the actual recorded temperature:
- At [tex]\( t = 5 \)[/tex]: Difference is [tex]\( |315 - 315.65| = 0.65 \)[/tex]
- At [tex]\( t = 10 \)[/tex]: Difference is [tex]\( |285 - 285.32| = 0.32 \)[/tex]
- At [tex]\( t = 15 \)[/tex]: Difference is [tex]\( |260 - 257.91| = 2.09 \)[/tex]
- At [tex]\( t = 20 \)[/tex]: Difference is [tex]\( |235 - 233.13| = 1.87 \)[/tex]
- At [tex]\( t = 25 \)[/tex]: Difference is [tex]\( |210 - 210.73| = 0.73 \)[/tex]

5. Determine the smallest difference: Identify which temperature has the smallest difference, indicating that the model prediction was closest to the actual temperature. The smallest difference here is 0.32, corresponding to the temperature 285°F at [tex]\( t = 10 \)[/tex] minutes.

6. Conclusion: The model most accurately predicts the temperature of 285°F as the time spent cooling. Therefore, with all considerations and analysis made, the most accurate prediction was made for the temperature of 285 degrees Fahrenheit.

I hope this helps clear up how to verify the model's accuracy at different temperatures! If you have any more questions or need further clarification, feel free to ask.