Chemistry - Ionic Equilibrium Question with Solution | TestHub

$K_c$ for the the reaction, $\left[\mathrm{Ag}(\mathrm{CN}{)}_2\right]\rightleftharpoons {\mathrm{Ag}}^{+}+2{\mathrm{CN}}^{-},$ the equillibrium constant at $25^{\circ }\mathrm{C}$ is $4.0\times 10^{-19}$ then the silver ion concentration in a solution which was originally 0.1 molar in $\mathrm{KCN}$ and 0.03 molar in ${\mathrm{AgNO}}_3$ is: