#include <bits/stdc++.h>
using namespace std;
int main() {
  int x, y, n, a, b, l = 0, r = 1;
  double min = INT_MAX;
  cin >> x >> y >> n;
  double xy = double(x) / y;
  while (r <= n) {
    double ab = double(l) / r;
    double dif = abs(ab - xy);
    if (dif < min) {
      min = dif;
      a = l;
      b = r;
    }
    if (ab > xy)
      r++;
    else
      l++;
    if (ab == xy) break;
  }
  cout << a << "/" << b;
}
