#include <bits/stdc++.h>
#pragma comment(linker, "/STACK:102400000,102400000")
using namespace std;
const int lowbit(int x) { return x & -x; }
const double eps = 1e-8;
const int INF = 1e9 + 7;
const long long inf = (1LL << 62);
const int MOD = 1e9 + 7;
const long long mod = (1LL << 32);
const int N = 2e5 + 10;
const int M = 100010;
template <class T1, class T2>
inline void getmax(T1 &a, T2 b) {
  if (b > a) a = b;
}
template <class T1, class T2>
inline void getmin(T1 &a, T2 b) {
  if (b < a) a = b;
}
int read() {
  int v = 0, f = 1;
  char c = getchar();
  while (c < 48 || 57 < c) {
    if (c == '-') f = -1;
    c = getchar();
  }
  while (48 <= c && c <= 57) v = v * 10 + c - 48, c = getchar();
  return v * f;
}
int n, k;
double l, v1, v2;
int p;
int main() {
  scanf("%d %lf %lf %lf %d", &n, &l, &v1, &v2, &k);
  double t = 0;
  p = n / k;
  if ((n % k) > 0) p++;
  t = l / (p * v2 - (v2 - v1) / (v1 + v2) * v2 * (p - 1));
  printf("%.7f\n", (l - v2 * t) / v1 + t);
  return 0;
}
