#include <bits/stdc++.h>
using namespace std;
int x, y, n;
void oku() { scanf("%d %d %d", &x, &y, &n); }
void coz() {
  int i, l, mnu, mna;
  double t, mn = 99999999, xx;
  t = x;
  t /= y;
  for (i = 1; i <= n; i++) {
    l = int(round(t * i - 0.0000001) + 0.0000001);
    xx = abs(((double)l) / i - t);
    if (mn > xx) {
      mn = xx;
      mnu = l;
      mna = i;
    }
  }
  printf("%d/%d\n", mnu, mna);
}
int main() {
  oku();
  coz();
  return 0;
}
