vous pouvez m'aider pour ce devoir s'il vous plaît ? ^^

Bonjour,

5/6 + 2/9

= (5 x 3) / (6 x 3) + (2 x 2) / (9 x 2)

= 15/18 + 4/18

= 19/18

3/4 + 3 + 5/6

= (3 x 3) / (4 x 3) + (3 x 12) / (1 x 12) + (5 x 2) / (6 x 2)

= 9/12 + 36/12 + 10/12

= 55/12

2,1 + 5/3

= (2,1 x 10) / (1 x 10) + 5/3

= 21/10 + 5/3

= (21 x 3) / (10 x 3) + (5 x 10) / (3 x 10)

= 63/30 + 50/30

= 113/30

1,8/3 + 1/7

= (1,8 x 10) / (3 x 10) + 1/7

= 18/30 + 1/7

= (6 x 3) / (6 x 5) + 1/7

= 3/5 + 1/7

= (3 x 7) / (5 x 7) + (1 x 5) / (7 x 5)

= 21/35 + 5/35

= 26/35

Réponse :

Bonjour

Explications étape par étape

5/6 + 2/9 = 15/18 + 4/18 = 19/18

3/4 + 3 + 5/6 = 9/12 + 36/12 + 10/12 = 55/12

2,1 + 5/3 = 21/10 + 5/3 = 63/30 + 50/30 = 113/30

1,8/3 + 1/7 = 18/30 + 1/7 = 6/10 + 1/7 = 42/70 + 10/70 = 52/70 = 26/35