#include<stdio.h>
#include<math.h>
int main(){
    float P,R;
    int N;
    if(scanf("%f %f %D",&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("%.2f ",emi);
    return 0;
}