#include <bits/stdc++.h>
#pragma comment(linker, "/STACK:16777216")
using namespace std;
string s;
int u, u1, q, w, n;
long double x, y, a, b, mini = 1000, k;
int main() {
  cin >> x >> y >> n;
  k = x / y;
  for (int i = n; i >= 1; i--) {
    u = int(i * x / y);
    u1 = u++;
    if (fabs(k - (long double)((long double)u / (long double)i)) <= mini) {
      mini = fabs(k - (long double)((long double)u / (long double)i));
      q = u;
      w = i;
    }
    if (fabs(k - (long double)((long double)u1 / (long double)i)) <= mini) {
      mini = fabs(k - (long double)((long double)u1 / (long double)i));
      q = u1;
      w = i;
    }
  }
  cout << q << "/" << w << endl;
  return 0;
}
