#include <iostream>
using namespace std;
#define rep(i,n) for(int i = 0; i < (n); i++)
#define ll double

int main(){
    ll n; cin >> n;
    ll g; cin >> g;
    ll v; cin >> v;
    ll res = 0;
    res = n / 5 * g / v;
    cout << res << endl;
    return 0;
}