Predicting a slot machine's payout is not possible, as modern slot machines use random number generators to determine the outcome of each spin. These random number generators ensure that each spin is independent of the previous one, making it impossible to predict the outcome with certainty.
While the results in slots are random and determined by a random number generator (RNG) within the game, there are some fixed parameters that determine the chance of winning. For example, the number of symbols for each type is fixed. More matching symbols on the reels can result in more frequent wins.