## Algebra: A Combined Approach (4th Edition)

2002: 29.0 miles per gallon 2003: 29.5 miles per gallon 2006: 30.25 miles per gallon 2007: 31.0 miles per gallon 2008: 31.25 miles per gallon From 2002 to 2003, $\frac{29.5-29.0}{2003-2002}=\frac{0.5}{1}=0.5$. From 2006 to 2007, $\frac{31.0-30.25}{2007-2006}=\frac{0.75}{1}=0.75$. From 2007 to 2008, $\frac{31.25-31.0}{2008-2007}=\frac{0.25}{1}=0.25$. 2006 to 2007 has the greatest slope.