#include <bits/stdc++.h>
using namespace std;
int main() {
  int x, y, n;
  while (scanf("%d%d%d", &x, &y, &n) != EOF) {
    int ansa = 0, ansb = 0;
    double dis = 100000000, tmp;
    for (int i = 1; i <= n; i++) {
      int a = (double)x * i / y;
      tmp = fabs(x * 1.0 / y - a * 1.0 / i);
      if (tmp < dis) {
        ansa = a;
        ansb = i;
        dis = tmp;
      }
      tmp = fabs(x * 1.0 / y - (a - 1) * 1.0 / i);
      if (tmp < dis) {
        ansa = a - 1;
        ansb = i;
        dis = tmp;
      }
      tmp = fabs(x * 1.0 / y - (a + 1) * 1.0 / i);
      if (tmp < dis) {
        ansa = a + 1;
        ansb = i;
        dis = tmp;
      }
    }
    printf("%d/%d\n", ansa, ansb);
  }
}
