#include <bits/stdc++.h>   using namespace std;   long long n, l, v1, v2, k;   long double dn, dl, dv1, dv2, dk;   long long times;   long double x;   double T;   int main() {     scanf( %lld%lld%lld%lld%lld , &n, &l, &v1, &v2, &k);     dn = n;     dl = l;     dv1 = v1;     dv2 = v2;     dk = k;     times = (n - 1) / k + 1;     x = l / (v2 * times - (dv2 - dv1) / (dv2 + dv1) * dv2 * (times - 1));     T = x * (times + (dv2 - dv1) / (dv2 + dv1) * (times - 1));     printf( %lf n , T);     return 0;   }   