The ‘x out of n’ calculator can be used to work out the value of promos like the one above. These are common on big race days, but you can also find them on sports like basketball, soccer, and NFL.

To win the bet above we would need James McDonald to win at least 2 races at the Gold Coast. However, before we even place the bet we first need to figure out if it has a positive expected value.

Calculating the true odds of JMac to have two winners would be easy if he was only riding in two races (we’d just multiply the lay odds of both his horses together). It becomes more complicated if he has more than two runners though. That is where the calc can help you.

If he was riding in five different races we would enter the lay odds for each of the five horses in the ‘Odds’ column. The calc will then tell us the probability and true odds for him having 1, 2, 3, 4, or 5 winners.

In this case, the true odds of him having 2+ runners are 2.27. That means that the 3.00 offered by Bet365 is good value and the bet is worth placing.

If the promo was for 3+ winners instead of 2+ we would need odds of above 7.47 for it to be worth considering.

Below are a couple of non-racing examples of where you could use this calculator. The process is exactly the same. You just enter the odds for all of the selections and the calc will tell you the odds for one to win, two to win, three to win etc.