To find the average speed of the cyclist, you can use the formula:
\[ \text{Average Speed} = \frac{\text{Total Distance}}{\text{Total Time}} \]
In this case, the total distance is 60.9 miles and the total time is 3.5 hours.
Now, substituting the values into the formula:
\[ \text{Average Speed} = \frac{60.9 \text{ miles}}{3.5 \text{ hours}} \approx 17.4 \text{ miles per hour} \]
So, the cyclist rode approximately 17.4 miles in one hour.