The equation y = 15.5x represents the number of dollars, y, Worker B earns in x hr. This means that Worker B earns $15.50 for every hour worked.
Of the answer choices, only y = 12x represents an earnings rate that is less than $15.50 per hour. Therefore, the equation y = 12x is the most likely equation to represent the number of dollars earned by Worker A.
The other answer choices, y = 13x, y = 15x, and y = 20x, all represent earnings rates that are greater than $15.50 per hour. This means that it is less likely that Worker A earns at these rates.
Therefore, the answer is **y = 12x**.