calculer astucieusement 17×72+17×28 12×17+3×12 121×4,01×21 1,005×8,5+3,995×8,5
Mathématiques
Lolo97195
Question
calculer astucieusement 17×72+17×28
12×17+3×12
121×4,01×21
1,005×8,5+3,995×8,5
12×17+3×12
121×4,01×21
1,005×8,5+3,995×8,5
2 Réponse
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1. Réponse nonotata
17×72+17×28 = 17(72+28) = 17(100) = 1700
12×17+3×12 = 12(17+3) = 12x20 = 240
121×4,01×21 = (100 +21)x4.01x21 = je ne vois pas
1,005×8,5+3,995×8,5 = 8.5 (1.005+3.995) =8.5(5) = 42.5 -
2. Réponse AntoñoDeJaneiro
Salut !
17×72+17×28 = 17 x (72+28) = 17 x 100 = 1700
12×17+3×12 = 12 x (17+3) = 12 x 20 = 240
121 x 4,01 x 21 = (100 +21) x 4.01 x 21 = aucune idée O_O
1,005 x 8,5+3,995 x 8,5 = 8.5 x (1.005+3.995) = 8.5 x 5 = 42.5
A bientôt !