#include<stdio.h>
int main(){
  long a,v,b,w,t;
  scanf("%ld %ld",&a,&v);
  scanf("%ld %ld",&b,&w);
  scanf("%ld",&t);
  if(a<b) {
  	if(b-a+(w-v)*t>0)printf("NO\n");
  	else printf("YES\n");
  }else{  	
    if(b-a+(w-v)*t>=0)printf("YES\n");
  	else printf("NO\n");
  }    
  return 0;
}