#include <bits/stdc++.h>
using namespace std;
int N;
int x[25252];
int y[25252];
int dx[25252];
int dy[25252];
int s[25252];
int main() {
  scanf("%d", &N);
  for (int i = 1; i <= N; i++)
    scanf("%d%d%d%d%d", &x[i], &y[i], &dx[i], &dy[i], &s[i]);
  double ans = 1e18;
  for (int i = 1; i <= N; i++) {
    for (int j = i + 1; j <= N; j++) {
      int det = dx[i] * (-dy[j]) - dy[i] * (-dx[j]);
      double veli = sqrt(dx[i] * dx[i] + dy[i] * dy[i]);
      double velj = sqrt(dx[j] * dx[j] + dy[j] * dy[j]);
      if (det == 0) {
        if ((y[j] - y[i]) * dx[i] != (x[j] - x[i]) * dy[i]) continue;
        int tx = x[j] - x[i];
        int ty = y[j] - y[i];
        if (tx) {
          if (dx[i] * tx < 0) {
            if (-dx[j] * tx < 0) {
              continue;
            } else
              ans = min(ans, fabs((double)tx / (s[j] * dx[j] / velj)));
          } else {
            ans = min(ans, fabs((double)tx / (s[i] * dx[i] / veli)));
            if (-dx[j] * tx > 0) {
              ans = min(ans, fabs((double)tx / (fabs(s[j] * dx[j] / velj) +
                                                fabs(s[i] * dx[i] / veli))));
            }
          }
        } else {
          if (dy[i] * ty < 0) {
            if (-dy[j] * ty < 0) {
              continue;
            } else
              ans = min(ans, fabs((double)ty / (s[j] * dx[j] / velj)));
          } else {
            ans = min(ans, fabs((double)ty / (s[i] * dx[i] / veli)));
            if (-dy[j] * ty > 0) {
              ans = min(ans, fabs((double)ty / (fabs(s[j] * dy[j] / velj) +
                                                fabs(s[i] * dy[i] / veli))));
            }
          }
        }
        continue;
      }
      int tx = x[j] - x[i];
      int ty = y[j] - y[i];
      int iu = -dy[j] * tx + dx[j] * ty;
      int iv = -dy[i] * tx + dx[i] * ty;
      if ((det > 0 && (iu < 0 || iv < 0)) || (det < 0 && (iu > 0 || iv > 0)))
        continue;
      double t1 = iu * veli / (det * s[i]);
      double t2 = iv * velj / (det * s[j]);
      ans = min(ans, max(t1, t2));
    }
  }
  if (ans == 1e18)
    puts("No show :(");
  else
    printf("%.10f\n", ans);
  return 0;
}
