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

int main(){
    
    float principle,rate ,emi;
    int n;
    scanf("%d %f %d",&principle,&rate,&n);
    
    rate=rate/(12*100);
    
    emi=(principle * rate * pow( 1+rate , n)) / (pow( 1+rate , n)) ;
    
    printf("%.2f",emi);
    
    return 0;
}