Bonjour pouvez vous m'aider à faire mon exercice s'il vous plaît : Calculez: A=3+9 sur 5 B=4 sur 9+ 5 su

Bonjour,

Calculez:

A=3+9/5
A = (3 x 5) / (1 x 5) + 9/5
A = 15/5 + 9/5
A = 24/5

B=4/9+ 5/6
B = (4 x 2) / (9 x 2) + (5 x 3) / (6 x 3)
B = 8/18 + 15/18
B = 23/18

C=(1/3-1/6)×6
C = [(1 x 2) / (3 x 2) - 1/6] x 6
C = (2/6 - 1/6) x 6
C = 1/6 x 6
C = 6/6
C = 1

D=5/7 - 3/7 x 2/3
D = 5/7 - 6/21
D = (5 x 3) / (7 x 3) - 6/21
D = 15/21 - 6/21
D = 9/21
D = (3 x 3) / (3 x 7)
D = 3/7

E= 2/5×5/4+4/5×10/8
E = 10/20 + 40/40
E = (10 x 2) / (20 x 2) + 40/40
E = 20/40 + 40/40
E = 60/40
E = (20 x 3) / (20 x 2)
E = 3/2

F= 7/5×(2/7+3/2)
F = 7/5 x [(2 x 2) / (7 x 2) + (3 x 7) / (2 x 7)]
F = 7/5 x (4/14 + 21/14)
F = 7/5 x 25/14
F = 175/70
F = (35 x 5) / (35 x 2)
F = 5/2

Bonjour

♧Calculez :

A = 3 + 9/5
A = (3×5)/(1×5) + 9/5
A = 15/5 + 9/5
A = (15+9)/5
A = 24/5

B = 4/9 + 5/6
B = (4×6)/(9×6) + (5×9)/(6×9)
B = 24/54 + 45/54
B = 69/54 = 23/18

C = (1/3 - 1/6) ×6
C = 1/6 × 6
C = 6/6 = 1

D = 5/7 - 3/7 × 2/3
--> La multiplication est prioritaire. .
D = 5/7 - (3/7 × 2/3)
D = 5/7 - 6/21
D = 15/21 - 6/21
D = 9/21 = 3/7

E = 2/5 × 5/4 + 4/5 × 10/8
--> les multiplications sont prioritaires. .
E = (2/5 × 5/4) + (4/5 × 10/8)
E = 10/20 + 40/40
E = 20/40 + 40/40
E = 60/40 = 6/4 = 3/2

F = 7/5 ×(2/7 + 3/2)
F = 7/5 × ( 4/14 + 21/14)
F = 7/5 × 25/14
F = 175/70 = 5/2

Voilà ^^