Solved: Weight of a Car versus Miles per Gallon(Refer to

Problem 21AYU

Answer:

Step1:

a). Here, Weight is the likely explanatory variable and miles per gallon is the likely response variable.

b).Scatter scatter diagram is obtained by using excel.

 Enter the data in a Excel sheet

 select all data given in problem

select scatter plot then press ok

From the above scatter plot we can say that there exists a negative correlation between two variables because as the value of x increases the value of y is decreasing.

c).

The linear correlation coefficient between the weight of a car and its miles per gallon in the city is calculated by using excel

 Enter the data in a Excel sheet

Go to Data Select data Analysis  select Correlation then ok

Enter the input range and output range and press ok

Therefore, the linear correlation coefficient between weight and height r = -0.95963.

d).The least-squares regression line is plotted by using excel

 Enter the data in a Excel sheet

 select all data given in problem

select scatter plot then press ok

to get regression line just right click on graph and select add trendline then select linear press close

Yes, from the above scatter plot we can notice that all plotted points falls almost near to the linear regression line therefore we can say that  negative linear relation exist between weight of a car and its miles per gallon in the city.

Step2:

Problem

a).The least-squares regression line treating