To find John's average speed in miles per hour (m.p.h.), you can use the formula:
\[ \text{Average Speed} = \frac{\text{Total Distance}}{\text{Total Time}} \]
In this case, the total distance is 8.8 miles, and the total time is 3 hours.
Now, plug in the values:
\[ \text{Average Speed} = \frac{8.8 \text{ miles}}{3 \text{ hours}} \approx 2.9333 \text{ m.p.h.} \]
Rounding to the nearest tenth:
\[ \text{Average Speed} \approx 2.9 \text{ m.p.h.} \]
So, John's average speed is approximately 2.9 m.p.h.