#include <bits/stdc++.h>
using namespace std;
int main() {
  int a, b, c;
  cin >> a >> b >> c;
  for (int i = 1; i <= 2; i++) {
    for (int j = 1; j <= 2; j++) {
      if (a * i + b * j >= c) {
        cout << "Yes" << endl;
        return 0;
      }
    }
  }
  cout << "No" << endl;
  return 0;
}
