Help with physics question on speed?

[CRYSTAL]

Here's the work problem:

John can run 5 meters in 1.82 sec. Therefore his average speed in running 5 m is 2.75 m/s. After this run, John runs 10 meters. He runs the 10 meter distance in 4.55 sec. Now he has an average speed of 4.40 m/s. Notice how after running the 10 meter distance, John's speed is greater. Does it make sense for John's speed to be greater? Why or why not?

-My teacher told me it did make sense, but told me to explain. I don't think the answer is "The greater the distance the greater the speed", because someone asked our teacher if the answer was right and I'm pretty sure they said no.
wait ahhh I'm sorry I made a mistake. The second time when John ran then he ran 20 meters, not 10.