#include <bits/stdc++.h>   using namespace std;   long long n, l, k, v1, v2;   bool chk(long double X) {     long double curr = 0;     long double nn = l;     long double f_time;     long double x = X;     for (long long i = 1; i < (n + k - 1) / k; i++) {       long double diss = nn - curr;       long double y = ((x * (long double)v1 * (long double)v2) -                        (l * (long double)v2) + (curr * (long double)v2)) /                       (long double)((long double)v1 - (long double)v2);       long double time = y / (long double)v2;       y += curr;       curr += (time * v1);       long double xx = ((y - curr) * (long double)v1) / (long double)(v1 + v2);       curr += xx;       f_time = (curr / (long double)v1);       x = X - f_time;     }     x -= ((l - curr) / (long double)v2);     return (x >= 0);   }   void query() {     cin >> n >> l >> v1 >> v2 >> k;     long double L = 0.0, R = l * (long double)v1, ans = R, diff = 1e-6;     while ((R - L) >= 1e-6) {       long double mid = (L + R) / 2.0;       if (chk(mid)) {         R = mid;         ans = min(ans, mid);       } else {         L = mid;       }     }     cout << setprecision(15) << ans <<   n ;   }   int32_t main() {     ios_base::sync_with_stdio(0);     cin.tie(0);     cout.tie(0);     ;     long long t = 1;     while (t--) {       query();     }   }   