Bonjour, pouvez vous m’aider à faire l’exercice svp

Bonjour

1)

A = 7/5 - 7/5 x 3/2

A = 7/5 - 21/10

A = (7 x 2) / (5 x 2) - 21/10

A = 14/10 - 21/10

A = - 7/10

B = (12/5 + 2/3) x 5/2

B = [(12 x 3) / (5 x 3) + (2 x 5) / (3 x 5)] x 5/2

B = (36/15 + 10/15) x 5/2

B = 46/15 x 5/2

B = 230/30

B = (10 x 23) / (10 x 3)

B = 23/3

C = 5/11 x 77/15 + 3/18

C = 385/165 + 3/18

C = (55 x 7) / (55 x 3) + (3 x 1) / (3 x 6)

C = 7/3 + 1/6

C = (7 x 2) / (3 x 2) + 1/6

C = 14/6 + 1/6

C = 15/6

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

C = 5/2

D = 19/5 - 3/5 x 4/3

D = 19/5 - 12/15

D = 19/5 - (3 x 4) / (3 x 5)

D = 19/5 - 4/5

D = 15/5

D = (5 x 3) / (5 x 1)

D = 3.

2)

A = - 0,7

B = 7,7

C = 7,2

D = 3.

Salut

[tex]\rule{7cm}{1mm}[/tex]

Exercice 61 :

1. Calculer les expressions suivantes, puis vérifier les résultats à la calculatrice.

A = 7 / 5 - 7 / 5 × 3 / 2

A = 7 / 5 - 7 × 3 / 5 × 2

A = 7 / 5 - 21 / 10

A = 7 × 2 / 5 × 2 - 21 / 10

A = 14 / 10 - 21 / 10

A = - 7 / 10

B = ( 12 / 5 + 2 / 3 ) × 5 / 2

B = ( 12 × 3 / 5 × 3 + 2 × 5 / 3 × 5 )

B = ( 36 / 15 + 10 / 15 ) × 5 / 2

B = 46 / 15 × 5 / 2

B = 2 × 23 / 5 × 3 × 5 / 2

B = 23 / 3

C = 5 / 11 × 77 / 15 + 3 / 18

C = 5 / 11 × 11 × 7 / 5 × 3 + 3 / 18

C = 7 / 3 + 3 / 18

C = 7 × 6 / 3 × 6 + 3 / 18

C = 42 / 18 + 3 / 18

C = 45 / 18

C = 5 / 2

D = 19 / 5 - 3 / 5 × 4 / 3

D = 19 / 5 - 3 × 4 / 5 × 3

D = 19 / 5 - 12 / 15

D = 19 × 3 / 5 × 3 - 12 / 15

D = 57 / 15 - 12 / 15

D = 45 / 15

2. Donner un arrondi au dixième des résultats.

A = -0,7

B ≃ 7,6

C = 2,5

D = 3