A macrostate is more likely in this model when more microstates land in its bucket. The comparison is not a new physical law; it is the same finite count ledger read as a probability ratio. Exact fractions make the ranking visible, while measured systems would require a separate argument that each listed microstate is equally available.
A larger probability can come from more realizations. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.
highlighted = computed this step
More realizations give the larger probability
The one-head bucket has more realizations than the zero-head bucket.
42>41
The comparison bit is part of the source
The comparison bit accepts the larger selected probability.