Cohabitating Households (thousands) example 5 Cohabitating Households The data in the table give the number of cohabiting (without marriage) households (in thousands) for selected years from 1960 to 2004. The scatter plot of these data, with x representing the number of years from 1950 and y representing thousands of households, is shown in the figure. Year Cohabitating Households (thousands) 1960 439 1993 3510 1970 523 1994 3661 1980 1589 1995 3668 1985 1983 1996 3958 1990 2856 1997 4130 1991 3039 1998 4236 1992 3308 2000 5476 2004 5841 Chapter 3.4 2009 PBLPathways

Cohabitating Households (thousands) The data in the table give the number of cohabiting (without marriage) households (in thousands) for selected years from 1960 to 2004. The scatter plot of these data, with x representing the number of years from 1950 and y representing thousands of households, is shown in the figure. Year Cohabitating Households (thousands) 1960 439 1993 3510 1970 523 1994 3661 1980 1589 1995 3668 1985 1983 1996 3958 1990 2856 1997 4130 1991 3039 1998 4236 1992 3308 2000 5476 2004 5841

Cohabitating Households (thousands) The data in the table give the number of cohabiting (without marriage) households (in thousands) for selected years from 1960 to 2004. The scatter plot of these data, with x representing the number of years from 1950 and y representing thousands of households, is shown in the figure. Year Cohabitating Households (thousands) 1960 439 1993 3510 1970 523 1994 3661 1980 1589 1995 3668 1985 1983 1996 3958 1990 2856 1997 4130 1991 3039 1998 4236 1992 3308 2000 5476 2004 5841 Find the power function that models these data. Graph the data and the model on the same axes.

Cohabitating Households (thousands) The data in the table give the number of cohabiting (without marriage) households (in thousands) for selected years from 1960 to 2004. The scatter plot of these data, with x representing the number of years from 1950 and y representing thousands of households, is shown in the figure. Year Cohabitating Households (thousands) 1960 439 1993 3510 1970 523 1994 3661 1980 1589 1995 3668 1985 1983 1996 3958 1990 2856 1997 4130 1991 3039 1998 4236 1992 3308 2000 5476 2004 5841 Find the power function that models these data.

Cohabitating Households (thousands) The data in the table give the number of cohabiting (without marriage) households (in thousands) for selected years from 1960 to 2004. The scatter plot of these data, with x representing the number of years from 1950 and y representing thousands of households, is shown in the figure. Years from 1950 Cohabitating Households (thousands) 10 439 43 3510 20 523 44 3661 30 1589 45 3668 35 1983 46 3958 40 2856 47 4130 41 3039 48 4236 42 3308 50 5476 54 5841 Find the power function that models these data.

Cohabitating Households (thousands) The data in the table give the number of cohabiting (without marriage) households (in thousands) for selected years from 1960 to 2004. The scatter plot of these data, with x representing the number of years from 1950 and y representing thousands of households, is shown in the figure. Years from 1950 Cohabitating Households (thousands) 10 439 43 3510 20 523 44 3661 30 1589 45 3668 35 1983 46 3958 40 2856 47 4130 41 3039 48 4236 42 3308 50 5476 54 5841 Find the power function that models these data.

The data in the table give the number of cohabiting (without marriage) households (in thousands) for selected years from 1960 to 2004. The scatter plot of these data, with x representing the number of years from 1950 and y representing thousands of households, is shown in the figure. Graph the data and the model on the same axes. y x

Enter the data To enter the data, press . Under the EDIT menu, press 1 or highlight 1: Edit... to enter the statistics editor. Enter each of the aligned year data in the first column. Press  or  after each number. Enter each of the cohabitating household data in the second column. Press  or  after each number.

Make the scatter plot Press . Enter the values shown to the right to insure all of the data pairs appear in the scatter plot. Press  to enter the STAT PLOT menu.

Press 1 or highlight 1: Plot 1 and  to adjust the scatter plot Press 1 or highlight 1: Plot 1 and  to adjust the scatter plot. Note that this menu displays the current settings for Plot 1. In this case, the plot is off, but set to make a scatter plot from lists L1 and L2 with the points being small boxes. Adjust the values for plot 1 to those shown to the right. If you did not place your data in lists L1 and L2, you’ll need to change the Xlist and Ylist appropriately.

To see the scatter plot, press  To see the scatter plot, press . If you see other points or the graph of a function, you’ll need clear those. If you see other data points, press  to turn off any extra stat plots. If you see graphs of functions, press . Move the cursor to the function and press .

Find the power model for the data Press . Move to the CALC menu by pressing . Scroll down using the  to A: PwrReg. Press  to paste the command to the home screen.

To supply the location of the data, press  To supply the location of the data, press . This means that the data in the list L1 corresponds to the independent variable and the data in the list L2 corresponds to the dependent variable. We would like to have the model pasted into the equation editor as Y1. To accomplish this, press . Move to the Y-Vars menu by pressing . Highlight 1: Function and press .

Highlight 1: Y1 and press  Highlight 1: Y1 and press . This pastes Y1 to the home screen to complete the command. To execute the command and find the model, press . The power model is displayed. We can display the model on the scatter plot by pressing .