/**
 *    author:  tourist
 *    created: 03.11.2019 18:59:19       
**/
#include <bits/stdc++.h>

using namespace std;

template <typename A, typename B>
string to_string(pair<A, B> p);

template <typename A, typename B, typename C>
string to_string(tuple<A, B, C> p);

template <typename A, typename B, typename C, typename D>
string to_string(tuple<A, B, C, D> p);

string to_string(const string& s) {
  return '"' + s + '"';
}

string to_string(const char* s) {
  return to_string((string) s);
}

string to_string(bool b) {
  return (b ? "true" : "false");
}

string to_string(vector<bool> v) {
  bool first = true;
  string res = "{";
  for (int i = 0; i < static_cast<int>(v.size()); i++) {
    if (!first) {
      res += ", ";
    }
    first = false;
    res += to_string(v[i]);
  }
  res += "}";
  return res;
}

template <size_t N>
string to_string(bitset<N> v) {
  string res = "";
  for (size_t i = 0; i < N; i++) {
    res += static_cast<char>('0' + v[i]);
  }
  return res;
}

template <typename A>
string to_string(A v) {
  bool first = true;
  string res = "{";
  for (const auto &x : v) {
    if (!first) {
      res += ", ";
    }
    first = false;
    res += to_string(x);
  }
  res += "}";
  return res;
}

template <typename A, typename B>
string to_string(pair<A, B> p) {
  return "(" + to_string(p.first) + ", " + to_string(p.second) + ")";
}

template <typename A, typename B, typename C>
string to_string(tuple<A, B, C> p) {
  return "(" + to_string(get<0>(p)) + ", " + to_string(get<1>(p)) + ", " + to_string(get<2>(p)) + ")";
}

template <typename A, typename B, typename C, typename D>
string to_string(tuple<A, B, C, D> p) {
  return "(" + to_string(get<0>(p)) + ", " + to_string(get<1>(p)) + ", " + to_string(get<2>(p)) + ", " + to_string(get<3>(p)) + ")";
}

void debug_out() { cerr << endl; }

template <typename Head, typename... Tail>
void debug_out(Head H, Tail... T) {
  cerr << " " << to_string(H);
  debug_out(T...);
}

#ifdef LOCAL
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#else
#define debug(...) 42
#endif

int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  int n;
  cin >> n;
  vector<int> a(n), b(n), delta(n);
  long long total = 0;
  for (int i = 0; i < n; i++) {
    cin >> a[i] >> b[i];
    delta[i] = max(b[i] - a[i], 0);
    total += delta[i];
  }
  vector<int> order(n);
  iota(order.begin(), order.end(), 0);
  sort(order.begin(), order.end(), [&](int i, int j) {
    return max(a[i], b[i]) < max(a[j], b[j]);
  });
  int add = 0;
  for (int i : order) {
    if (max(a[i], b[i]) <= total) {
      total -= max(a[i], b[i]);
      ++add;
    } else {
      break;
    }
  }
  debug(add, total);
  long long num = 0, den = 1;
  for (int it = 0; it < n; it++) {
    int i = order[it];
    long long new_total = total;
    if (it < add) {
      new_total += max(a[i], b[i]);
      new_total -= max(a[order[add]], b[order[add]]);
      if (new_total < 0) {
        continue;
      }
    }
    new_total -= max(a[i], b[i]);
    long long cur_num = max(0LL, b[i] + new_total);
    long long cur_den = b[i];
    if (cur_num * den > num * cur_den) {
      num = cur_num;
      den = cur_den;
    }
  }
  num += add * den;
  den *= n;
  long long g = __gcd(num, den);
  num /= g;
  den /= g;
  cout << num << " " << den << '\n';
  return 0;
}


Measured memory_bytes: 1792