Digital Cable Subscribers The number of subscribers to dig- ital cable television has been growing steadily, as shown by the
following table. Source: National Cable and Telecommuni- cations Association.
|
Year
|
2000
|
2002
|
2004
|
2006
|
2008
|
|
Customers (in millions)
|
8.5
|
19.3
|
25.4
|
32.6
|
40.4
|
a. Find an equation for the least squares line, letting x equal the number of years since 2000.
b. Based on your answer to part a, at approximately what rate is the number of subscribers to digital cable television growing per year?
c. Use your result from part a to predict the number of digital cable subscribers in the year 2012.
d. If this trend continues linearly, in what year will the number of digital cable subscribers ?rst exceed 70 million?
e. Find and interpret the correlation coefficient.