#include <bits/stdc++.h>
using namespace std;
int32_t main() {
  int64_t x, y, n;
  cin >> x >> y >> n;
  double dis = 1e10;
  int64_t a = 0, b = 0;
  for (int64_t i = 1; i <= n; i++) {
    int64_t num = (double)i * x / y;
    double tmp;
    tmp = abs(x * 1.0 / y * 1.0 - num * 1.0 / i * 1.0);
    if (tmp < dis) {
      dis = tmp;
      a = num, b = i;
    }
    tmp = abs(x * 1.0 / y * 1.0 - (num + 1) * 1.0 / i * 1.0);
    if (tmp < dis) {
      dis = tmp;
      a = num + 1;
      b = i;
    }
  }
  cout << a << "/" << b << endl;
  return 0;
}
