intros n1 n2 d H'; apply Fle_Fge; auto.
apply Fle_Zle; auto.
apply Zge_le; auto.
Qed.

(* Specifications: *)
Lemma Flt_Fgt : forall x y : float, Flt x y -> Fgt y x.
unfold Flt, Fgt in |- *; intros x y H'; auto.