From Figure 1, the best odds for the said match is tabulated in table 1. First, we find the total market value of the odds using this formula:

Market = 1/Outcome 1 + 1/Outcome 2+ 1/Outcome 3

Market = 1/2.25 + 1/3.5 + 1/3.6 = 100.79%

As of the moment, the total market value of the odds is 100.79%. If the market value drops below 100%, it creates an arb and will be a sure profit for the bettor if he bets on all events. If for example, Paddy power, Stan James or Winner add 0.1 on their current odds of Everton winnning, the Market value becomes:

Market = 1/2.35 + 1/3.5 + 1/3.6 = 98.60%

This gives the bettor a 1.10% profit margin, no matter the result of the game. This is the called the arbitrage percentage. We may write this condition in a formula for an event with N event outcomes:

1 / O1 + 1 / O2 + ... + 1 /ON < 1

where O1 is Outcome 1, O2 is Outcome 2 and ON is Outcome N. For a sporting event with only two outcome, we can easily derive a formula that we can use to spot an arb (assuming that the odds are always positive):

1 / O1 + 1/O2 < 1

1 / O1 < 1 - 1/O2

O1 < (1 - 1/O2)^-1

Plotting this formula in Figure 2, we can see that all Odds combination under the curve are non-arb bets. In contrary, all odds combination over the curve are arbitrary bets.