#include <stdio.h>
#include <math.h>

int main(){
    double P, R, N;
    double EMI;
    
    if (scanf("%1f %1f %1f", &P, &R, &N) != 3) {
        printf("Invalid input\n");
        return 1;
    }
    R = (R / 100) / 12;
    if (N == 0) {
        printf("Invalid input\n");
        return 0;
    }
    EMI = (P * R * pow(1 + R, N)) / (pow(1+ R, N) - 1);
    printf("%.2f\n", EMI);
    return 0;
}