#include <bits/stdc++.h>
using namespace std;
bool isPrime(int N) {
  for (int i = 2; i * i <= N; ++i) {
    if (N % i == 0) return false;
  }
  return true;
}
bool sortinrev(const pair<int, int> &a, const pair<int, int> &b) {
  return (a.first > b.first);
}
int gcd(int a, int b) {
  if (b == 0) return a;
  return gcd(b, a % b);
}
bool comp(const pair<int, int> &a, const pair<int, int> &b) {
  return (a.second > b.second);
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  double k, i, j, n, sum = 0, s, x, y, diff = 1000000000, b, a, num, den;
  cin >> x >> y >> n;
  for (b = 1; b <= n; b++) {
    long long op1, op2;
    op1 = (b * x) / y;
    op2 = (b * x) / y + 1;
    double d1 = abs((x / y) - abs(op1 / b));
    double d2 = abs((x / y) - abs(op2 / b));
    if (d1 < diff) {
      diff = d1;
      num = op1;
      den = (long long)b;
    }
    if (d2 < diff) {
      diff = d2;
      num = op2;
      den = (long long)b;
    }
  }
  cout << num << "/" << den << endl;
  return 0;
}
