(Before tackling this, you might like to look back to WMC 290, which offered some inspiration!)

After settling their argument over the cake, Arglbzz, Brthflum and Clonk are having some races.

The first race is between Arglbzz and Brthflum. They each start at opposite ends of a large field and run towards each other at a constant speed. They meet 440m away from where Arglbzz started.

Next, Arglbzz races Clonk. They meet 396m away from where Arglbzz started.

Finally, Brthflum races Clonk. They meet 450m away from where Brthflum started.

How long is the field? (In other words, how far apart did the aliens start each race?)