#include<stdio.h>
#include<math.h>
int main(){
    double p,r,n;
    scanf("%lf %lf %lf",&p,&r,&n);
    if(p<=0||r<=0||n<=0){
        printf("Invalid input");
        return 0;
    }
    double r=r/(12*100);
    double emi=(p*r*pow(1+r,n))/(pow(1+r,n)-1);
    printf("%.2lf",emi);
    return 0;
}