#include <bits/stdc++.h>
using namespace std;
int main() {
  int x, y, n, a, b;
  cin >> x >> y >> n;
  long double d = 10000000000, t, q;
  t = (long double)x / y;
  for (int i = 1; i <= n; i++) {
    q = abs(t - floor(t * i) / i);
    if (q < d) {
      a = floor(t * i);
      b = i;
      d = q;
    }
    q = abs(t - ceil(t * i) / i);
    if (q < d) {
      a = ceil(t * i);
      b = i;
      d = q;
    }
  }
  cout << a << "/" << b << endl;
  return 0;
}
