#include <bits/stdc++.h>
const int inf = 0x3f3f3f3f, Inf = 0x7fffffff;
const long long INF = 0x7fffffffffffffff;
__inline__ __attribute__((always_inline)) unsigned int rnd() {
  static unsigned int seed = 0x05ad13b4;
  return seed ^= seed >> 5, seed ^= seed << 17, seed ^= seed >> 13;
}
template <typename _Tp>
_Tp gcd(const _Tp &a, const _Tp &b) {
  return (!b) ? a : gcd(b, a % b);
}
template <typename _Tp>
__inline__ __attribute__((always_inline)) _Tp abs(const _Tp &a) {
  return a >= 0 ? a : -a;
}
template <typename _Tp>
__inline__ __attribute__((always_inline)) _Tp max(const _Tp &a, const _Tp &b) {
  return a < b ? b : a;
}
template <typename _Tp>
__inline__ __attribute__((always_inline)) _Tp min(const _Tp &a, const _Tp &b) {
  return a < b ? a : b;
}
template <typename _Tp>
__inline__ __attribute__((always_inline)) void chmax(_Tp &a, const _Tp &b) {
  (a < b) && (a = b);
}
template <typename _Tp>
__inline__ __attribute__((always_inline)) void chmin(_Tp &a, const _Tp &b) {
  (b < a) && (a = b);
}
template <typename _Tp>
__inline__ __attribute__((always_inline)) void read(_Tp &x) {
  char ch(getchar());
  bool f(false);
  while (ch < 48 || ch > 57) f |= ch == 45, ch = getchar();
  x = ch & 15, ch = getchar();
  while (ch >= 48 && ch <= 57)
    x = (((x << 2) + x) << 1) + (ch & 15), ch = getchar();
  if (f) x = -x;
}
template <typename _Tp, typename... Args>
__inline__ __attribute__((always_inline)) void read(_Tp &t, Args &...args) {
  read(t);
  read(args...);
}
__inline__ __attribute__((always_inline)) int read_str(char *s) {
  char ch(getchar());
  while (ch == ' ' || ch == '\r' || ch == '\n') ch = getchar();
  char *tar = s;
  *tar = ch, ch = getchar();
  while (ch != ' ' && ch != '\r' && ch != '\n' && ch != EOF)
    *(++tar) = ch, ch = getchar();
  return tar - s + 1;
}
const int N = 25005;
const double eps = 1e-8;
__inline__ __attribute__((always_inline)) int dcmp(const double &a) {
  return a > eps ? 1 : a < -eps ? -1 : 0;
}
int x[N], y[N], dx[N], dy[N], s[N];
double k[N], b[N];
double v[N];
int main() {
  int n;
  read(n);
  for (int i = 1; i <= n; ++i) {
    read(x[i], y[i], dx[i], dy[i], s[i]);
    int g = gcd(abs(dx[i]), abs(dy[i]));
    dx[i] /= g, dy[i] /= g;
    k[i] = (double)dy[i] / dx[i];
    b[i] = y[i] - k[i] * x[i];
    v[i] = abs((double)s[i] *
               ((double)dx[i] / sqrt(dx[i] * dx[i] + dy[i] * dy[i])));
  }
  double ans = 1e18;
  for (int i = 1; i <= n; ++i) {
    for (int j = i + 1; j <= n; ++j) {
      if (dcmp(k[i] - k[j]) == 0) {
        if (dcmp(b[i] - b[j]) != 0) continue;
        if (dx[i] == dx[j]) {
          if (dx[i] > 0) {
            if (x[j] > x[i]) {
              chmin(ans, (x[j] - x[i]) / v[i]);
            } else {
              chmin(ans, (x[i] - x[j]) / v[j]);
            }
          } else {
            if (x[j] > x[i]) {
              chmin(ans, (x[j] - x[i]) / v[j]);
            } else {
              chmin(ans, (x[i] - x[j]) / v[i]);
            }
          }
        } else {
          if ((x[i] < x[j] && dx[i] > 0) || (x[i] > x[j] && dx[i] < 0)) {
            chmin(ans, abs(x[i] - x[j]) / (v[i] + v[j]));
          }
        }
      } else {
        double X = (b[i] - b[j]) / (k[j] - k[i]);
        if (dcmp(X - x[i]) == 1 && dx[i] < 0) continue;
        if (dcmp(X - x[i]) == -1 && dx[i] > 0) continue;
        if (dcmp(X - x[j]) == 1 && dx[j] < 0) continue;
        if (dcmp(X - x[j]) == -1 && dx[j] > 0) continue;
        chmin(ans, max(abs(X - x[i]) / v[i], abs(X - x[j]) / v[j]));
      }
    }
  }
  if (ans > 1e17)
    printf("No show :(\n");
  else
    printf("%.12lf\n", ans);
  return 0;
}
