To find the average speed in meters per second, you'll need to convert the marathon distance from miles to meters and the time from hours and minutes to seconds.
1 mile = 1,609.34 meters (approximately)
1 hour = 3,600 seconds
1 minute = 60 seconds
So, the marathon distance in meters is:
26 miles * 1,609.34 meters/mile = 41,841.64 meters
The time in seconds is:
3 hours * 3,600 seconds/hour + 40 minutes * 60 seconds/minute = 13,200 seconds
Now, you can calculate the average speed:
Average Speed (meters per second) = Distance (meters) / Time (seconds)
Average Speed = 41,841.64 meters / 13,200 seconds ≈ 3.17 meters per second
The average speed of the runner in meters per second is approximately 3.17 m/s.