#include <bits/stdc++.h>
const double INF = 2000000000000;
int x, y, n;
int main() {
  scanf("%d%d%d", &x, &y, &n);
  double fr = (double)x / y;
  int ansa, ansb;
  double min = INF;
  for (int b = 1; b <= n; ++b) {
    double aa = (double)fr * b;
    int ca = (int)aa;
    for (int a = ca - 5; a <= ca + 5; ++a) {
      double fr1 = (double)a / b;
      if (fabs(fr - fr1) < min) {
        ansa = a;
        ansb = b;
        min = fabs(fr - fr1);
      }
    }
  }
  printf("%d/%d\n", ansa, ansb);
}
