Réponses

2014-09-18T22:31:50+02:00
C = 3/8 : 5
C = 3/8 x 1/5
C = 3/40

D = 7 - 1/5
      7 + 1/5
D = 7 x 5 / 1 x 5 - 1/5
      7 x 5 / 1 x 5 + 1/5
D = 35/5 - 1/5
      35/5 + 1/5
D = 34/5 : 36/5
D = 34/5 x 5/36
D = 170/180
D = 10 x 17 / 10 x 18
D = 17/18

E = 2/9 - (3/10 + 4/5)
E = 2/9 - (3/10 + 4 x 2 / 5 x 2)
E = 2/9 - (3/10 + 8/10)
E = 2/9 - 11/10
E = 2 x 10 / 9 x 10 - 11 x 9 / 10 x 9
E = 20/90 - 99/90
E = - 79/90

F = (- 4/7 + 2/7) x 5/6
F = (- 2/7) x 5/6
F = - 10/42
F = 2 x - 5 / 2 x 21
F = - 5/21

G = 3 : 8/5
G = 3 x 5/8
G = 15/8