Bonjour,

on met au même dénominateur:

10/12 + 4/12 = 14/12

9/12 +5/12 = 14/12

21/12 -7/12  = 14/12

7/6 = 14/12

10/8  = 5/4 = 15/12

donc on supprime (5*2)/(4*2)

13/24 +3/24 + 12/24 =28/24 = 14/12

14/12

13/6 - 6/6 = 7/6 = 14/12

40/24 - 10/24 -1/24 = 29/24

On supprime 5/3 -5/12 -1/24

bonjour

ligne  1

5/6 + 2/6  = 7 /6

9/12 + 5/12 = 14/12 = 7/6

21/12 - 7 /12 = 14 /12 = 7 /6

ligne  2

7/6

10/8 = 5/4

13/24 + 3/24 + 12/24 =  28/24= 7/6

ligne  3

14/12 = 7/6

13/6 - 6/6 = 7/6

40/24 - 10/24 - 1/24 = 29/24