Alternatively, maybe the calculator is for the player to calculate how many balls they might need to aim for a Hole-in-One, based on probability.
In this example, the chance is higher if the club power is closer to the effective distance, and adjusted by accuracy and skill bonus.
In reality, in many games, the probability of a Hole-in-One might be determined by certain stats. For example, maybe the player's accuracy, the strength of the club, the distance to the hole, terrain modifiers, etc. So the calculator could take these inputs and compute the probability.