I have seen the “Olympic”, “Standard”, or “International” distance sometimes referred to as the “5150”, yet I had never been able to figure out why, or whether the references were with respect to a different race.
Then I started playing geek games with my calculator:
1500 m swim + 40 km bike + 10 km run = 51.50 km
With a factor of 100 between friends, that becomes “5150”.
World Triathlon Corp’s 5150 Triathlon Series site does list the distances at the bottom of each page, but doesn’t add it up for you. For everyone else like me who hadn’t found that, or didn’t do the math, here you go.