[jgunnip]

Well first i believe you need a hand, then to go with that I think you opponent needs a hand. It looks like this is a situation where the button pushed and you're trying to figure out if you should call. This is entirely hand dependent since you have to calculate the chance your hand has vs his range of hands. then put what you've got here, with the percetnage chance that the even will happen and you've're on your way. also including the stack sizes before the hand was dealt is also helpful.