#include <bits/stdc++.h>
using namespace std;
int main() {
  double x, y, n;
  while (cin >> x >> y >> n) {
    double a, b;
    double dis = 1e10;
    int ansup = 0;
    int ansdown = 0;
    for (b = 1; b <= n + 1e-7; b++) {
      double tmp = 1e10;
      double l, r, mid;
      l = 0;
      r = 1e5;
      while (r - l > (1 - 1e-5)) {
        a = (l + r) / 2;
        if (a / b > x / y) {
          r = (l + r) / 2;
        } else
          l = (l + r) / 2;
        double cnt = (int)a;
        tmp = abs(x / y - cnt / b);
        if (tmp < dis || tmp == dis && cnt < ansup) {
          dis = tmp;
          ansup = (int)cnt;
          ansdown = b;
        }
      }
      double tmp1 = abs(x / y - 0 / b);
      double tmp2 = abs(x / y - 1 / b);
      if (tmp1 == tmp2) {
        if (tmp1 <= dis + 1e-7 &&
            ((ansdown > b) || (ansdown == b && ansup > 0))) {
          dis = tmp;
          ansup = 0;
          ansdown = b;
        }
      } else if (tmp1 != tmp2) {
        if (abs(dis - tmp1) < abs(dis - tmp2) &&
            ((ansdown > b) || (ansdown == b && ansup > 0)) &&
            tmp1 <= dis + 1e-7) {
          dis = tmp1;
          ansup = 0;
          ansdown = b;
        } else if (abs(dis - tmp1) > abs(dis - tmp2) &&
                   ((ansdown > b) || (ansdown == b && ansup > 1)) &&
                   tmp2 <= dis + 1e-7) {
          dis = tmp2;
          ansup = 1;
          ansdown = b;
        }
      }
    }
    cout << ansup << "/" << ansdown << endl;
  }
  return 0;
}
