A larger signal raises occupancy without changing the receptor constant. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.

highlighted = computed this step

Higher signal changes the denominator too

The high signal is 18 with the same half-signal constant 6.

18+6=2418+6=24
Receptor occupancy ledgerA half-signal constant turns signal into a bound fraction.183/4

The high-side occupancy is three fourths

The high-side bound fraction is 3/4.

18/24=3418/24=\frac{3}{4}
Receptor occupancy ledgerA half-signal constant turns signal into a bound fraction.183/4