bonjour je comprends pas cette exercice pour demain pouvez vous m'aider ?​

Bonjour,

A = 2/5 + 4/3 x 9/7

A = 2/5 + 36/21

A = 2/5 + (3 x 12) / (3 x 7)

A = 2/5 + 12/7

A = (2 x 7) / (5 x 7) + (12 x 5) / (7 x 5)

A = 14/35 + 60/35

A = 74/35

B = 15/2 : 24/5

B = 15/2 x 5/24

B = 75/48

B = (3 x 25) / (3 x 16)

B = 25/16

C = (8 - 5/3) x (1/4 + 7/12)

C = [(8 x 3) / (1 x 3) - 5/3] x [(1 x 3) / (4 x 3) + 7/12]

C = (24/3 - 5/3) x (3/12 + 7/12)

C = 19/3 x 10/12

C = 190/36

C = (2 x 95) / (2 x 18)

C = 95/18.

D = 9/4 + 5

     3 - 2/8

D = 9/4 + (5 x 4) / (1 x 4)

     (3 x 8) / (1 x 8) - 2/8

D = 9/4 + 20/4

      24/8 - 2/8

D = 29/4 : 22/8

D = 29/4 x 8/22

D = 232/88

D = (8 x 29) / (8 x 11)

D = 29/11.