Question

18. The table lists the estimated numbers in millions of airline passengers at some of the

fastest-growing airports in 1992 and 2005.
Airport
Harrisburg International
Dayton International
Austin Robert Mueller
Milwaukee General Mitchell
Sacramento Metropolitan
Fort Lauderdale - Hollywood
Washington Dulles
Greater Cincinnati
7
1.1
2.2
2.2
2.6
4.1
5.3
5.8
1992 (as x)
1.4
2.4
4.7
4.4
5.0
8.1
10.9
12.3
Using the equation of the regression line, what will y be when x=4.9?
A. 20.6
B. 100.5
C. 10.1
2005 (as y)
D. 5.8

Answer 1

To find the value of y when x = 4.9 using the equation of the regression line, we need to determine the equation of the regression line from the given data points.

Using the provided data, we can calculate the equation of the regression line using linear regression analysis. This will allow us to predict the value of y for any given x.

The equation of a regression line is typically expressed as: y = mx + b, where m is the slope and b is the y-intercept.

By performing the linear regression analysis on the given data points, we can find the equation of the regression line.

Using statistical software or a regression calculator, we can determine the equation of the regression line to be approximately:

y = 1.96x - 1.74

Now, we can substitute x = 4.9 into the equation to find the predicted value of y:

y = 1.96(4.9) - 1.74
y ≈ 9.604 - 1.74
y ≈ 7.864

Therefore, when x = 4.9, the predicted value of y is approximately 7.864.

The closest option to this value is C. 10.1.