Average speed= total distance / total time
Distance 1 = 300 meters
Distance 2 = 300 meters (back)
Total distance = 300m+300m = 600 meters
Time 1= 10 minutes
Time 2 = 2 minutes
Total Time = 10min+2min=12 minutes
Average speed= 600 meters / 12 minutes = 50 meters/minute
