5KM in Under Twenty Five Minutes

So as of a few days ago, I'm invited to a 5KM event, marking the creation of a new bridge linking the island to Busan.

It will open at the weekend, and I have had the past few days to train for the event.

My aim is to run the 5KM in 25 minutes or less.

The only problem is, I don't know what my average speed should be.  I went balls out on the treadmill, only to fail at 3.75 KM.  It later transpired that my pace would have put me in a sub-twenty minute zone, should I have succeeded.

I therefore need the internets to work out what my average pace should be.

One man, a weeks training and ten thousand won.

Can he do it?  Only time will tell.