#include <bits/stdc++.h>
using namespace std;
int x, y, lim;
int main() {
  scanf("%d %d %d", &x, &y, &lim);
  long double frac = (long double)x / y;
  int a = 0, b = 1;
  for (int i = 1; i <= lim; i++) {
    if (abs((floor(frac * i) / i) - frac) < abs((long double)a / b - frac)) {
      a = floor(frac * i);
      b = i;
    }
    if (abs((ceil(frac * i) / i) - frac) < abs((long double)a / b - frac)) {
      a = ceil(frac * i);
      b = i;
    }
  }
  printf("%d/%d", a, b);
  return 0;
}
