Preparing one supplies the second exact row of the assignment matrix. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.
highlighted = computed this step
Prepared one gives a second row
When one is prepared, the readout counts are 2 zero decisions and 8 decisions of one.
Nread zero=2,Nread one=8
This row also closes to one
The second row is 1/5 and 4/5. These fractions come from the same total of 10.