#include <bits/stdc++.h>
using namespace std;
const int N = 25005;
int x[N], dx[N], y[N], dy[N], n;
double v[N];
double sol(int a, int b) {
  int kk = dx[b] * dy[a] - dy[b] * dx[a];
  if (kk != 0) {
    double r = 0, rr = 0;
    r = x[a] * dy[a] + y[b] * dx[a] - y[a] * dx[a] - x[b] * dy[a];
    rr = y[b] * dx[b] + x[a] * dy[b] - y[a] * dx[b] - x[b] * dy[b];
    r /= (1.0 * kk * v[b]);
    rr /= (1.0 * kk * v[a]);
    if (min(r, rr) < 0)
      return -1;
    else
      return max(r, rr);
  } else {
    if ((x[b] - x[a]) * dy[a] != (y[b] - y[a]) * dx[a])
      return -1;
    else {
      double aa = (x[a] * dx[a] + y[a] * dy[a]),
             bb = (x[b] * dx[a] + y[b] * dy[a]),
             v1 = (dx[a] * dx[a] + dy[a] * dy[a]) * v[a],
             v2 = (dx[b] * dx[a] + dy[b] * dy[a]) * v[b];
      double t = -1;
      if (v1 * (bb - aa) > 0 && v2 * (aa - bb) > 0)
        t = (bb - aa) / (v1 - v2);
      else if (v1 * (bb - aa) > 0)
        t = (bb - aa) / v1;
      else if (v2 * (aa - bb) > 0)
        t = (aa - bb) / v2;
      return t;
    }
  }
}
signed main() {
  double ans = -1;
  scanf("%d", &n);
  for (int i = 1; i <= n; i++)
    scanf("%d%d%d%d%lf", &x[i], &y[i], &dx[i], &dy[i], &v[i]),
        v[i] /= sqrt(dx[i] * dx[i] + dy[i] * dy[i]);
  for (int i = 1; i < n; i++) {
    for (int j = i + 1; j <= n; j++) {
      double now = sol(i, j);
      if (now >= 0) {
        if (ans < 0)
          ans = now;
        else
          ans = min(ans, now);
      }
    }
  }
  if (ans < 0)
    puts("No show :(");
  else
    printf("%0.12lf\n", ans);
  return 0;
}
