#include <bits/stdc++.h>
using namespace std;
const int inf = 1e9 + 5;
const int nax = 1e6 + 5;
int main() {
  int n, total, v1, v2, k;
  scanf("%d%d%d%d%d", &n, &total, &v1, &v2, &k);
  if (k == n) {
    printf("%.10lf\n", (double)total / v2);
    return 0;
  }
  int kursy = (n + k - 1) / k;
  double g1, g2;
  g1 = g2 = 0;
  g1 = v1;
  g2 = v2;
  double tajm = 1;
  for (int _ = (0); _ <= ((kursy - 1) - 1); ++_) {
    double x = (g2 - g1) * v1 / (v1 + v2);
    double dif = x / v1;
    tajm += dif;
    g1 += dif * v1;
    g2 += dif * v1;
    dif = (g2 - g1) / (double)(v2 - v1);
    tajm += dif;
    g1 += dif * v1;
    g2 += dif * v1;
  }
  printf("%.10lf\n", tajm * (double)total / g2);
  return 0;
}
