A finite squared-residual budget can reject a drifting run. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.
highlighted = computed this step
A drifting run can average away from the target
Readings 8, 10, 12, 14 volts average to 11 volts.
Vˉ=11V
The squared residual budget rejects the run
Residuals -2, 0, 2, 4 give budget 24, which is above limit 4, so accepted bit is 0.