#include <bits/stdc++.h>
using namespace std;
#define si(a) (long)a.size()
#define fi first
#define se second
#define all(x) x.begin(),x.end()
#define rep(i,n) for(int i=0;i<(int)(n);++i)
template<typename S,typename F>bool chmin(S&a,F b){return b<a?(a=b,1):0;}
template<typename S,typename F>bool chmax(S&a,F b){return b>a?(a=b,1):0;}
bool _=(ios::sync_with_stdio(0),cin.tie(0),cout<<fixed<<setprecision(16),0);


int main(){
    int A,B,C,D,S;
    cin>>A>>B>>C>>D>>S;
    cout<<(A*C+B*D<=S?"Yes\n":"No\n");
}