Two solids A and D dissociated into gaseous products as follows:

$\begin{array}{r}A\left(s\right)\rightleftharpoons B\left(g\right)+C\left(g\right):K_{P_1}=300\\ D\left(s\right)\rightleftharpoons E\left(g\right)+C\left(g\right):K_{P_2}=600\end{array}$

at ${27}^{\circ }C,$, then find the total pressure (in atm) of the solid mixture.