#include <bits/stdc++.h>
using namespace std;
double x, y, n;
double mmin;
int gcd(int a, int b) {
  if (b == 0)
    return a;
  else
    return gcd(b, a % b);
}
int main() {
  cin >> x >> y >> n;
  mmin = 100000;
  if (y < n) {
    int temp = gcd(x, y);
    cout << x / temp << "/" << y / temp << endl;
  } else {
    double s = x / y;
    double a, b, aa, bb;
    for (b = 1; b <= n; b++) {
      a = (int)(s * b);
      if (fabs(s - a / b) < mmin) {
        mmin = fabs(s - a / b);
        aa = a;
        bb = b;
      }
      a = (int)(s * b) + 1;
      if (fabs(s - a / b) < mmin) {
        mmin = fabs(s - a / b);
        aa = a;
        bb = b;
      }
    }
    cout << aa << "/" << bb << endl;
  }
  return 0;
}
