// editor1
#include <stdio.h>
#include <math.h>
int main(){
    double P,R,N;
    
    double *pP = &P;
    double *pR = &R;
    double *pN = &N;
    
    if (scanf("%lf %lf %lf", pP, pR, pN)= 3){
        printf("Invalid input");
        return 0;
        
    }
    if(*pN == 0){
        printf("Invalid input");
        return 0;
    }
    double Rx = (*pR)/(12 * 100);
    double pow_val = pow(1 + Rx, *pN);
    double EMI = (*pP) * Rx * pow_val / (pow_val - 1);
    printf("%.2f", EMI);
    return 0;
}