Question

1. The 2010 census reported about 308.7 million people in the United States. The 2000 census reported a population of about 281.4 million. By about what percent did the population change? Did the population grow or shrink?

Answer 1

Let C be the percentage change. 
C = 100*(308.7 million - 281.4 million)/(281.4 million) = 9.7%. This is positive, so the population grew. 
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