Concept explainers
Use of Cellular Telephones The following table shows the subscribership of cellular telephones in the United States (in millions) for selected years between 2000 and 2012. Source: The World Almanac and Book of Facts 2014.
Year | 2000 | 2004 | 2008 | 2012 |
Subscribers (in millions) | 109.48 | 182.14 | 270.33 | 326.48 |
(a) Plot the data by letting t = 0 correspond to 2000. Discuss how well the data fit a straight line.
(b) Determine a linear equation that approximates the number of subscribers using the points (0, 109.48) and (12, 326.48).
(c) Repeat part (b) using the points (4, 182.14) and (12, 326.48).
(d) Discuss why your answers to parts (b) and (c) are similar but not identical.
(e) Using your equations from parts (b) and (c), approximate the number of cellular phone subscribers in the year 2010. Compare your result with the actual value of 296.29 million.
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Finite Mathematics (11th Edition)
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