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Less gas? Refer to Exercise 38.

a. Interpret the slope of the regression line.

b. Does the value of the y intercept have meaning in this context? If so, interpret the y intercept. If not, explain why.

Short Answer

Expert verified

Part (a) The average amount of natural gas Joan will consume per day over the course of a month reduces by 19.87cubic feet per degree Fahrenheit.

Part (b) It does not have meaning.

Step by step solution

01

Part (a) Step 1: Given information

It is stated in the regression line question that,

y=142519.87x

02

Part (a) Step 2: Explanation

As we know, the slope in the least square regression equation is the coefficient of x and indicates the average rise or decrease of y per unit of x Thus, the slope is,

b1=19.87

As a result, the average amount of natural gas Joan will consume per day over the course of a month reduces by 19.87 cubic feet per degree Fahrenheit.

03

Part (b) Step 1: Explanation

The y-intercept, as we all know, is a constant in the least square regression equation that reflects the average y-value when x is 0 As a result, the y-intercept is:

b0=1425

When the temperature is 0 degrees Fahrenheit, this means that the average amount of natural gas utilized per day is 1425 cubic feet. The y-intercept has meaning in this instance because a temperature of 0 degrees Fahrenheit is feasible.

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