A betting odds table lays these prices side by side: formats in columns, implied chance in the last one. Reading such a table is quick practice. Evens sits at a fifty per cent chance, odds of 1.50 at about sixty seven, odds of 4.00 at twenty five, and odds of 11.00 near nine. Seeing the column of chances next to the prices makes it plain how fast the chance falls as the payout grows.
The same numbers read differently by sport. In horse racing, betting odds work across a large field, so each runner carries a long price and the chances across the field add up well past one hundred per cent. In soccer, a match has three outcomes, home, draw and away, and the draw takes a share of the probability. A moneyline in sports with no draw simply names a winner, with a favourite at short odds and an underdog at a long price.
To interpret betting odds, turn the price into two numbers: the payout and the implied chance. At decimal odds of 3.00 a stake of ten returns thirty, so the betting odds payout is thirty with twenty of it profit. The implied chance is one in three. If the event happens more often than that over many tries, the price is generous; if less often, the price is short. Every other reading of a price rests on those two numbers.