A certain drawing states that the odds of winning are 15:270. What would be the odds against winning?

3 answers

270-15 = 255
odds of losing = 255:270
NOTE: odds of winning + odds of losing should= 1
270:15
There must be 285 results, 15 that win, and 270 that lose.
As I understand it, the May 1 answer from Anonymous is talking about probability, not odds. The probability of winning is 15/270 which reduces to 1/18. The probability of losing is 255/270 which reduces to 17/18.
Odds are wins to losses, 15:270 or 1 to 18. So the odds of losing are 270:15 or 18 to 1.