#include <bits/stdc++.h>
using namespace std;
using ll=long long;
const int INF=1e9;

int main() {
	cin.tie(nullptr),cout.tie(nullptr);
	ios::sync_with_stdio(false);
  
  int a,b,c,d,e ;
  cin >> a >> b >> c >> d >> e;
  
int x=(a*c)+(b*d);
    if(x<=e){
  cout << "Yes" << endl;
  return 0;
    }
  cout << "No" << endl;
}