#include <bits/stdc++.h>
long long ago;
using namespace std;
template <class T = long long int>
T nxt() {
  T x;
  cin >> x;
  return x;
}
long long int pw(long long int a, long long int b, long long int mod) {
  if (!b) return 1;
  if (b & 1) return a * pw(a * a % mod, b / 2, mod) % mod;
  return pw(a * a % mod, b / 2, mod) % mod;
}
const long long int N = 1000 + 10;
const long long int INF = 8e18;
const long long int MOD = 1e9 + 7;
long long int n, m, mark[N];
double dist[N], S[N], Z[N];
vector<pair<long long int, double>> adj[N];
priority_queue<pair<double, long long int>, vector<pair<double, long long int>>,
               greater<pair<double, long long int>>>
    pq;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr);
  cout.tie(nullptr);
  cout << setprecision(15) << fixed;
  cin >> n;
  for (long long int i = 1; i <= n; i++) {
    for (long long int j = 1; j <= n; j++) {
      long long int p = nxt();
      if (i == j || p == 0) continue;
      adj[j].emplace_back(i, double(p) / 100);
    }
  }
  fill(Z, Z + N, 1.0);
  fill(dist, dist + N, INF);
  dist[n] = 0;
  pq.push({0, n});
  while (!pq.empty()) {
    long long int u = pq.top().second;
    pq.pop();
    if (mark[u]) continue;
    mark[u] = 1;
    for (auto [v, p] : adj[u]) {
      if (mark[v]) continue;
      S[v] += Z[v] * p * (dist[u] + 1);
      Z[v] *= (1 - p);
      dist[v] = (S[v] + Z[v]) / (1 - Z[v]);
      pq.push({dist[v], v});
    }
  }
  cout << dist[1] << '\n';
  return 0;
}
