#include <bits/stdc++.h>

#define REP(i,l,u) for(int (i)=(int)(l);(i)<(int)(u);++(i))

using namespace std;

typedef int64_t ll;

const int INF = 1e8;
const double EPS = 1e-10;

int main() {
    ios_base::sync_with_stdio(false);
    ll N;
    double G, V;
    cin >> N >> G >> V;
    printf("%.11lf\n", ((N/5LL) * G / V));
}