Verified answer

bonjour

ex 1

1)  101 x 17 = (100 + 1) x 17 = 100 x 17 + 1 x 17 = 1700 + 17 = 1717

2)  99 x 13 = (100 - 1) x 13 = 100 x 13 - 1 x 13 = 1300 - 13 = 1287

3) 1002 x 14 = (1000 + 2) x 14 = 14000 + 2 x 14 = 14000 + 28 = 14028

4)  98 x 22 = (100 - 2) x 22 = 2200 - 44 = 2156

5)  5,4 x 7 + 5,4 x 3 = 5,4 x (7 + 3) = 5,4 x 10 = 54

6)  8 x 19 + 2 x 19 = 19 x (8 + 2) = 19 x 10 = 190

7)  96 x 5 + 4 x 5 = 5 x (96 + 4) = 5 x 100 = 500

8)  13 x 103 - 3 x 13 = 13 x (103 - 3) = 13 x 100 = 1300

9)  21 x 999 + 21 = 21 x (999 + 1) = 21 x 1000 = 21000

ex 2

calculer de 2 façons différentes

   •  4 x (7 + 5) = 4 x 12 = 48

      4 x (7 + 5) = 4 x 7 + 4 x 5 = 28 + 20 = 48

  • 4 x 3 + 5 x 3 = 12 + 15 = 27

    4 x 3 + 5 x 3 = 3 x (4 + 5) = 3 x 9 = 27

de même pour les autres