intros; unfold Fle, FtoRradix, FtoR in |- *; simpl in |- *; auto.
case Zle_lt_or_eq with (1 := H); intros H1.
apply Rlt_le; auto with real.
rewrite <- H1; auto with real.
Qed.

Lemma Flt_Zlt :
forall n1 n2 d : Z, (n1 < n2)%Z -> Flt (Float n1 d) (Float n2 d).