#include<stdio.h>
#include<math.h>
int main(){
    float p,r,n;
    if(scanf("%f %lf %lf",&p,&r,&n)!=3){
        printf("Invalid Input");
        return 0;
    }
    if(n==0){
        printf("Invalid Input");
        return 0;
    }
    float monthlyrate=r/(12*100);
    float numerator=p*monthlyrate*pow(1+monthlyrate,n);
    float denominator=pow(1+monthlyrate,n)-1;
    float emi=0;
    if(denominator!=0)
        emi=numerator/denominator;
    printf("%.2lf ",emi);
    return 0;
}