#include <stdio.h>
#include <math.h>
int main(){
    double P, R, EMI, power = 1;
    int N, i;
    scanf("%lf %lf %d", &P, &R,&N);
    if(P <= || R <= 0 || N <= 0 ){
        printf("Invalid input");
        return 0;
    }
    R = R / (12 * 100);
    for(int = 1; i <= N; i++){
        power = power * (1 + R);
    }
    EMI = (P * R * power) / (power - 1);
    printf("%.2f", EMI);
    return 0;
    
}