#include <bits/stdc++.h>
using namespace std;
int main() {
  int x, y, n;
  cin >> x >> y >> n;
  long double min = 1e19;
  pair<int, int> ans;
  long double res = (double)x / y;
  for (int i = 1; i <= n; i++) {
    int a = res * i;
    long double dif = (double)a / i;
    dif = abs(res - dif);
    if (dif < min) {
      min = dif;
      ans.first = a;
      ans.second = i;
    }
    a++;
    dif = (double)a / i;
    dif = abs(res - dif);
    if (dif < min) {
      min = dif;
      ans.first = a;
      ans.second = i;
    }
  }
  cout << ans.first << "/" << ans.second << endl;
}
