#include <bits/stdc++.h>
using namespace std;
int main() {
  int x, y, n;
  cin >> x >> y >> n;
  double mn = 99999999;
  int ra, rb;
  for (int i = 1; i <= n; ++i) {
    int tx = round(1.0 * x * i / y - 0.0000001);
    if (fabs((1.0 * x / y) - (1.0 * tx / i)) < mn) {
      ra = tx;
      rb = i;
      mn = fabs((1.0 * x / y) - (1.0 * tx / i));
    }
  }
  cout << ra << "/" << rb;
  return 0;
}
