To find out how long Tyrone was walking, you can use the formula:
\[ \text{Time} = \frac{\text{Distance}}{\text{Speed}} \]
In this case, the distance is 8 miles and the speed is 2 miles per hour.
\[ \text{Time} = \frac{8 \text{ miles}}{2 \text{ miles per hour}} = 4 \text{ hours} \]
So, Tyrone was walking for 4 hours.