Answer: 12.5% decrease
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Step-by-step explanation:
The decrease is 0.4 million since 3.2 - 2.8 = 0.4
Divide this decrease over the initial population
0.4/3.2 = 0.125
This converts to 12.5% when you move the decimal 2 spots to the right.
The population decreased by 12.5%