On emission of 2 alpha particles, mass number is reduced by 8 and atomic number by 4 .
${}_{\mathrm{z}}{\mathrm{S}}^{\mathrm{A}}\to {\mathrm{z}}_{-4}{\mathrm{Q}}^{\mathrm{A}-8}+2{}_2{\mathrm{He}}^4$
Now, on emission of 1 beta particle, mass number remains same but atomic number increases by 1 .
$\mathrm{z}-4{\mathrm{Q}}^{\mathrm{A}-8}\to \mathrm{Z}-3{\mathrm{R}}^{\mathrm{A}-8}+{}_{-1}^0\mathit{\beta }$
After decay, given element is ${}_{85}{\mathit{R}}^{222}$. Therefore
$\mathit{A}-8=222\Rightarrow \mathit{A}=230$
(Atomic Mass)
$\mathrm{Z}-3={85}^{\circ }\Rightarrow \mathrm{Z}=88$
(Atomic No.)