Speed = Distance / Time
Distance = 10 000 m
time = 27 minutes 30.42 seconds.
27 minutes = 27*60 seconds = 1620 seconds
time = 27 minutes 30.42 seconds = 1620 seconds + 30.42 seconds = 1650.42 seconds
Speed = 10000 m / 1650.42s ≈ 6.059 m/s
Average speed ≈ 6.059 m/s
Hope this helps.