Answer
There was a population increase of $3$ million per year from $2000$ to $2010.$
Work Step by Step
Determine the increase (or decrease) in population by subtracting the population in $2000$ from the population in $2010$:
$310\text{ million} - 280\text{ million} = 30\text{ milllion}$
Determine the time elapsed (in years) by subtracting $2000$ from $2010$:
$2010 - 2000 = 10\text{ years}$
There was a $30$ million increase in population in $10$ years.
Determine the annual rate of change by dividing $10$ to the increase in population to obtain:
$\text{annual rate of change}=\dfrac{30\text{ million}}{10\text{ years}}=3\text{ million per year}$
Therefore, the annual rate of change in the population from $2000$ to $2010$ was $3$ million.
