Exercice 3 et 4 page 84 4 eme Mercii

Bonjour, voici la réponse à tes exercices :

Exercice n°3

1. 5/6 + 3/14 = (5 × 7) / (6 × 7) + (3 × 3) / (14 × 3) = 35/42 + 9/42 = 44/42

2. 44/42 = (22 × 2) / (21 × 2) = 22/21

Exercice n°4

a. 1/2 + 7/5

= (1 × 5) / (2 × 5) + (7 × 2) / (5 × 2)

= 5/10 + 14/10

= 19/10

b. 8/7 - 7/12

= (8 × 12) / (7 × 12) - (7 × 7) / (12 × 7)

= 96/84 - 49/84

= 47/84

c. 2/23 - 11/10

= (2 × 10) / (23 × 10) - (11 × 23) / (10 × 23)

= 20/230 - 253/230

= - 233/230

d. - 3/4 - 7/9

= - (3 × 9) / (4 × 9) - (7 × 4) / (9 × 4)

= - 27/36 - 28/36

= (- 27 - 28) / 36

= - 55/36

En espérant t'avoir aidé au maximum !