Concept explainers
Population Aging The following table shows the percentage of U.S. residents over the age of 65 in 1950, 1960, …, 2010:38
Year t (years since 1900) | 50 | 60 | 70 | 80 | 90 | 100 | 110 |
Percentage P over 65 (%) | 8.2 | 9.2 | 9.9 | 11.3 | 12.6 | 12.6 | 13 |
a. Find the logarithmic regression model of the form
b. In 1940, 6.9% of the population was over age 65. To how many significant digits does the model reflect this figure?
c. Which of the following is correct? The model, if extrapolated into the indefinite future, predicts that
(A) The percentage of U.S. residents over the age of 65 will increase without bound.
(B) The percentage of U.S. residents over the age of 65 will level off at around 14.2%.
(C) The percentage of U.S. residents over the age of 65 will eventually decrease.
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