Two radioactive elements R and S disintegrate as `RtoP+alpha,lamda_(R)=4.5xx10^(-3)|'years|'^(-1)`

Two radioactive elements R and S disintegrate as `RtoP+alpha,lamda_(R)=4.5xx10^(-3)\"years\"^(-1)` `StoQ+betal,lamda_(S)=3xx10^(-3)\"years\"^(-1)` Starting with number of atoms of R and S in the ratio of 2:1 this ratio afte4r the lapse of three half lives of R will be

`RtoP+alpha,lamda_(R)=4.5xx10^(-3)\"years\"^(-1)`