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Suppose a sportsbook offers Team A at +120 and Team B at −145. Implied probabilities:
  • For +x odds: p=100/(x+100)p = 100/(x+100)
  • For -y odds: p=y/(100+y)p = y/(100+y)
Thus:
  • pA∗=100/(120+100)≈45.45p^*_A = 100/(120+100) \approx 45.45%%
  • pB∗=145/(145+100)≈59.18p^*_B = 145/(145+100) \approx 59.18%
  • pA∗+pB∗=104.63p^*_A + p^*_B = 104.63% → embedded vig
Normalize (de-juice):
  • pA=pA∗/(pA∗+pB∗)≈43.44p_A = p^*_A/(p^*_A+p^*_B) \approx 43.44%%
  • pB=pB∗/(pB∗+pA∗)≈56.56p_B = p^*_B/(p^*_B+p^*_A) \approx 56.56%
Converted back to American odds, this is roughly +131 and -131.