#include <bits/stdc++.h>
using namespace std;
int main() {
  ios::sync_with_stdio(false);
  double x, y, n;
  cin >> x >> y >> n;
  double dis = 999999;
  int X, Y;
  for (double h = 1; h <= n; ++h) {
    double w1 = ceil((h * x) / y), w2 = floor((h * x) / y);
    if (fabs(h * x - w1 * y) < fabs(h * x - w2 * y)) {
      if (dis > fabs((x / y) - (w1 / h)))
        dis = fabs((x / y) - (w1 / h)), X = w1, Y = h;
    } else {
      if (dis > fabs((x / y) - (w2 / h)))
        dis = fabs((x / y) - (w2 / h)), X = w2, Y = h;
    }
  }
  cout << X << "/" << Y << endl;
  return 0;
}
