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Multiple choice
A 2×22\times 2 readout confusion matrix is A=[abcd]=[0.900.050.100.95]A = \begin{bmatrix}a & b \\ c & d\end{bmatrix} = \begin{bmatrix}0.90 & 0.05 \\ 0.10 & 0.95\end{bmatrix}, mapping true probabilities to measured ones. Measured probabilities are (pMeas0,pMeas1)=(0.4,0.6)(p_\text{Meas0}, p_\text{Meas1}) = (0.4, 0.6). Inverting (det⁡=ad−bc\det = ad - bc), the corrected pTrue0=(d pMeas0−b pMeas1)/det⁡p_\text{True0} = (d\,p_\text{Meas0} - b\,p_\text{Meas1})/\det. What is pTrue0p_\text{True0}?