To calculate the average speed, you can use the formula:
\[ \text{Average speed} = \frac{\text{Total distance}}{\text{Total time}} \]
In this case, Kerry drove 180 miles in 3.0 hours. Plugging in the values:
\[ \text{Average speed} = \frac{180 \text{ miles}}{3.0 \text{ hours}} = 60 \text{ miles/hour} \]
Therefore, the average speed is 60 miles/hour.