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(* as published by the Free Software Foundation; either version 2.1   *)
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(* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the      *)
(* GNU General Public License for more details.                       *)
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(* 02110-1301 USA                                                     *)
Require Export Max.

Lemma le_mult_mult : forall n m p q : nat, n <= m -> p <= q -> n * p <= m * q.