#include <stdio.h>
#include <string.h>

int main()
{
  char buf1[8];
  char buf2[8];
  char buf3[8];
  char *p;
  int A, V, B, W, T;
  
  fgets(buf1, 4, stdin);
  fgets(buf2, 4, stdin);
  fgets(buf3, 4, stdin);
  
  p = strtok(buf1, " ");
  A = strtol(buf1, 10);  
  p = strtok(NULL, " ");
  V = strtol(buf1, 10);  
  
  p = strtok(buf2, " ");
  B = strtol(buf2, 10);  
  p = strtok(NULL, " ");
  W = strtol(buf2, 10);  
  
  T = strtol(buf3, 10);  
  
  if(A + V * T >= B + W * T) printf("YES");
  else printf("NO");
}
