#include<stdio.h>
#include<math.h>
int main(){
    int p,r,n;
    scanf("%d %d %d",&p,&r,&n);
    
    if(p<=0 || r<=0 || n<=0){
        printf("Invalid Input");
        return 0;
    }
    r=r/(12*100);
    
    if(ratepower == 1)
    {
        printf("Invalid Input");
        return 0;
    }
    double EMI =(p * r *ratepower)/(ratepower -1);
    printf("%.3f",EMI); 
    return 0;
}