U.S. population With U.S. Census Bureau data (actual and projected) for selected years from 1960 to 2050, the rate of change of U.S. population P can be modeled by
dP/dt = 20.0002187t2 + 0.0276t + 1.98
million people per year, where t = 0 represents 1960.
(a) In what year does this rate of change reach its maximum?
(b) In 1960, the U.S. population was 181 million. Use this to find a model for P(t).
(c) For 2025, the Census Bureau's predicted U.S. population is 348 million. What does the model predict?