Bonjour aidez moi silv.

Bonjour,

a) 7/3 - 5/21

= (7 x 7) / (3 x 21) - 5/21

= 49/21 - 5/21

= 44/21

b) 3 + - 2/5 - 18/20

= (3 x 20) / (1 x 20) - (2 x 4) / (5 x 4) - 18/20

= 60/20 - 8/20 - 18/20

= 60/20 - 26/20

= 34/20

= (2 x 17) / (2 x 10)

= 17/10

c) 3 + (5/8 - 10/16)

= 3 + [(5 x 2) / (8 x 2) - 10/16]

= (3 x 16) / (1 x 16) - (10/16 - 10/16)

= 48/16 - 0

= 48/16

= (16 x 3) / (16 x 1)

= 3

d) - 4/10 + (2 + 3/- 30)

= - 4/10 + (2 - 1/10)

= - 4/10 + [(2 x 10) / (1 x 10) - 1/10]

= - 4/10 + (20/10 - 1/10)

= - 4/40 + 19/10

= 15/10

= (5 x 3) / (5 x 2)

= 3/2.

Réponse :

Bonjour

Explications étape par étape

7/3 - 5/21

= (7 x 7)/(7 x 3) - 5/21

= 49/21 - 5/21

= 44/21

3 + (-2/5) - 18/20

= (3 x 20)/(1 x 20) - (2 x 4)/(5 x 4) - 18/20

= 60/20 - 8/20 - 18/20

= 60/20 - 26/20

= 34/20

= (2 x 17)/(2 x 10)

= 17/10

3 + (5/8 - 10/16)

= (3 x 16)/(1 x 16) + (5 x 2)/(8 x 2) - 10/16

= 48/16 + 10/16 - 10/16

= 48/16

= (16 x 3)/(16 x 1)

= 3

-4/10 + (2 + 3/-30)

= (-4 x 3)/(10 x 3) + (2 x 30)/(1 x 30) - 3/30

= -12/30 + 60/30 - 3/30

= 60/30 - 15/30

= 45/30

= (15 x 3)/(15 x 2)

= 3/2