#include <bits/stdc++.h>
using namespace std;
pair<double, pair<int, int> > min(pair<double, pair<int, int> > a,
                                  pair<double, pair<int, int> > b) {
  if (abs(a.first - b.first) < 1e-15)
    return a.second.first < b.second.first ? a : b;
  return std::min(a, b);
}
int main(void) {
  double x, y, n;
  double a;
  pair<double, pair<int, int> > ans(100000000.0, pair<int, int>(0, 0));
  cin >> x >> y >> n;
  for (int b = 1; b <= n; b++) {
    a = (ceil(x * b / y));
    ans = min(ans, pair<double, pair<int, int> >(
                       abs(x / y - a / b), pair<int, int>(b, (int)(a + 1e-8))));
    a = (floor(x * b / y));
    ans = min(ans, pair<double, pair<int, int> >(
                       abs(x / y - a / b), pair<int, int>(b, (int)(a + 1e-8))));
  }
  cout << ans.second.second << "/" << ans.second.first << endl;
  return 0;
}
