#include <bits/stdc++.h>
using namespace std;
int main() {
  int a, b, x, y, n, sol1, sol2;
  cin >> x >> y >> n;
  float c = (float)x / y;
  float ans = 1000000000, tmp;
  for (int i = n; i > 0; i--) {
    a = (int)(c * i) + 1;
    tmp = abs(((float)a / i) - c);
    if (ans >= tmp) {
      ans = tmp;
      sol1 = a;
      sol2 = i;
    }
    a = a - 1;
    tmp = abs(((float)a / i) - c);
    if (ans >= tmp) {
      ans = tmp;
      sol1 = a;
      sol2 = i;
    }
  }
  cout << sol1 << "/" << sol2;
  return 0;
}
