#include <bits/stdc++.h>
using namespace std;
const long long inf = INT_MAX;
const long double ep = 0.0000001;
const long double pi = acos(-1.0);
const long long md = 1e9 + 7;
long long gcd(long long x, long long y) {
  if (y == 0) return x;
  return gcd(y, x % y);
}
void solve() {
  long double x, y, n;
  cin >> x >> y >> n;
  long long g = gcd((long long)x, (long long)y);
  x /= g, y /= g;
  if (n >= y) {
    cout << x << '/' << y;
    return;
  }
  long double mn = 1e9;
  pair<long long, long long> p;
  while (n) {
    long double a = round((long double)x * n / y - ep);
    if (abs(x / y - a / n) <= mn) {
      p = make_pair(a, n);
      mn = abs(x / y - a / n);
    }
    n--;
  }
  cout << p.first << '/' << p.second;
}
signed main() {
  ios_base::sync_with_stdio(false);
  long long t = 1;
  while (t--) solve();
}
