Kowane fadar cetiya ce ta gida. Juyar da decimal odds zuwa probability ta tumanin ba da wahala: raba 1 da odds. Odds na 2.00 ta nuna 50%, odds na 4.00 ta nuna 25%, odds na 1.25 ta nuna 80%. Juyar da wannan ne tushe na kowane yanke-shawarar cetiya mai muhimmanci, domin ya baje ta 'shin wannan fadar ba?' zuwa tambaya mai amsa 'shin wannan probability ba ya yi kaba?'.
Tara-tara probability da tumanin na kowane sakamako a kasuwar ce ta nuna margin na bookmaker: jumi duka ya wuce 100%, kuma yadda ya wuce shine gida na ma'aikin cetiya. Cire wannan margin ne ya ba da fair probabilities — ra'ayin kasuwar da gaske — da waje da ake auna value.
Wasa da aka fadi a 2.10 (gida), 3.60 (jiya), 3.40 (baƙi) ta nuna 47.6% + 27.8% + 29.4% = 104.8%. Abin 4.8% shine margin na bookmaker; probability na gida da ya dace bayan cire shi daidai shine 47.6 / 104.8 ≈ 45.4%.