#include <bits/stdc++.h>
using namespace std;
double X, Y;
long double best = 1e16;
int N;
int main() {
  cin >> X >> Y >> N;
  int retA, retB, A;
  for (int den = 1; den <= N; den++) {
    A = floor(X * den / Y);
    if (fabs(X / Y - (long double)A / den) < best) {
      retA = A;
      retB = den;
      best = fabs(X / Y - (long double)A / den);
    }
    A = ceil(X * den / Y);
    if (fabs(X / Y - (long double)A / den) < best) {
      retA = A;
      retB = den;
      best = fabs(X / Y - (long double)A / den);
    }
  }
  cout << retA << "/" << retB << endl;
}
