\(\begin{array}{l}
Dat\,n_{NaCl}=x(mol);n_{NaBr}=y(mol)\\
\to 58,5x+113y=11(1)\\
NaCl+AgNO_3\to AgCl↓+NaNO_3\\
NaBr+AgNO_3\to AgBr↓+NaNO_3\\
Theo\,PT:\,n_{AgCl}=x(mol);n_{AgBr}=y(mol)\\
\to 143,5x+188y=23,75(2)\\
(1)(2)\to x=0,1;y=0,05\\
\to m_{NaCl}=0,1.58,5=5,85(g);m_{NaBr}=11-5,85=5,15(g)
\end{array}\)