Question

(a) What is the predicted heating cost for a month with an average temperature of 0 F? (b) What is the predicted heating cost for a month with an average temperature of 25 F ) ? (c) For an increase of one degree Fahrenheit, what is the predicted decrease in the monthly heating cost ?

Answer 1

Part A:

$96.30

Part B:

$65.55

Part C:

$1.23

Explanation:

Part A:

To find the predicted heating cost for a month with an average temperature of 0 F, we use x as 0 in the equation of the line of best fit, as following:

`\begin{gathered} y=-1.23x+96.30 \\ \rightarrow y=-1.23(0)+96.30 \\ \Rightarrow y=96.30 \end{gathered}`

Therefore, we can conclude that the answer is $96.30

Part B:

To find the predicted heating cost for a month with an average temperature of 25 F, we use x as 25 in the equation of the line of best fit, as following:

`\begin{gathered} y=-1.23x+96.30 \\ \rightarrow y=-1.23(25)+96.30 \\ \Rightarrow y=65.55 \end{gathered}`

Therefore, we can conclude that the answer is $65.55

Part C:

In this question we're being asked about the slope of the line. From the equation of the line of best fit, we can conclude that the slope is -1.23.

Therefore, we can conclude that for an increase of one degree Fahrenheit, the predicted decrease in the monthly heating cost is $1.23