An exact threshold tie is not guessed in this model; it triggers a repeat rule so the finite decision table stays explicit. The tie behavior is exact only for equality to the declared threshold and ideal digitization; real systems use dead bands, confidence thresholds, finite resolution, noise filtering, and repeat-shot statistics.
An exact threshold tie is handled explicitly by repeating the readout. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.
highlighted = computed this step
Equality is not guessed
A signal exactly equal to threshold 5 is assigned the repeat rule, not zero or one.
5=5⇒repeat
The dead band here is only equality
This book uses a narrow tie rule: only exact equality at 5 repeats the measurement.