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