With horse racing odds, the first number (the numerator) shows how many units you stand to win, and the second number (the denominator) shows how many units you must risk to win that much. The “fraction” represents the relationship between how much you stand to win relative to how much you must risk.
Similarly, when a horse is priced at 3-5, one can read that as 3/5. When a horse is priced at 10-1, one can read that as 10/1.
Horse racing betting odds are essentially fractions.
