A finite residual budget is scanned across wider readings. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.
highlighted = computed this step
The gate uses squared residuals
The checked source has target ten and limit four. Its accepted bit comes from the residual budget, not from the average alone.
(−1)2+12=2
A wider run can cross the same gate limit
The target and limit stay fixed. The squared budget grows from zero to eight, so the last row is rejected.