#include <stdio.h>
#include <math.h>
int main(){
    double P, R_annual_percent,R_monthly, EMI;
    int N;
    // Read P , R, N
    if (scanf("%1f %1f %d",&P, &R_annual_percent, &N)!= 3){
        return 1;
    }
   // Calculate monthly interest rate(R_monthly = R_annual percentage rate R_monthly = R_annual_percent / 1200.0);
   if (R_monthly == 0.0){
       // Simple case: no interest EMI = (N > 0) ? (P / N) : 0.0;
   } else {
       // Calculatr (1+R)^N double power_term = pow(1.0 + R_monthly, N);
       // EMI = [P *R *(1+R)^N] / [(1+R)^N-1]
       EMI = [P * R * (1+R)^N]/[(1+R)^N-1]
       EMI = (P * R_monthly * power_term) / (power_team - 1.0);
   }
   //Print result formatted to two decimal places
   printf("%.2f\n", EMI);
   return 0;
}