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{\mathcal B}(t\bar{t} \rightarrow \colorbox{red}{\bf \color[rgb]{0,1,0} W b Z c}) = 
\frac{ N_\mathrm{candidates} - N_\mathrm{background} }
{{\mathcal A} \cdot \int {\mathcal L} dt \cdot \sigma_{t \bar{t}}}
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