Odds, Probability & Bankroll

This category covers the arithmetic behind every bet: the three ways odds are written, how to turn a price into a probability, where the house edge comes from, and the staking ideas people use to manage a bankroll.

Most confusion here is notation rather than mathematics. 5/2, 3.50 and +250 are one identical price written for three different markets, and a page explaining only one of them leaves you stuck the moment you look at a different sportsbook. Read the format pages first, then the margin pages — that pairing accounts for most of what people find puzzling.