Final answer:
The population decreased by 10,600 from 2010 to 2015, to the nearest 100 people.
Step-by-step explanation:
To find the decrease in population from 2010 to 2015, we need to calculate the population in 2015 and then subtract the population in 2010.
Given that the population in 2010 was 212,000, and it grew by 5% from 2010 to 2015, we can calculate the population in 2015 by multiplying 212,000 by 1 + 5/100. This gives us 212,000 * 1.05 = 222,600.
Next, we know that the population fell by 3% from 2015 to 2020. We can calculate the population in 2020 by multiplying 222,600 by 1 - 3/100. This gives us 222,600 * 0.97 = 215,982.
To find the decrease from 2010 to 2015, we subtract the population in 2010 from the population in 2015: 222,600 - 212,000 = 10,600.
Therefore, the population decreased by 10,600 from 2010 to 2015, to the nearest 100 people.