HELP!!! Calculer chaque expression et donner le résultat sous la forme d'une fraction la +simple possible (merci de me détailler les réponses pour que je compre

N° I
A = 3/7 * (7/3 - 5/6)
A = 3/7 x (7 x 2 / 3 x 2 - 5/6)
A = 3/7 x (14/6 - 5/6)
A = 3/7 x 9/6
A = 3 x 9
      7 x 6
A = 27/42
A = 3 x 9 / 3 x 14
A = 9/14

B = 3/7 * 7/3 - 5/6
B = 3 x 7 - 5/6
      7 x 3
B = 21/21 - 5/6
B = 21 x 2 / 21 x 2 - 5 x 7 / 6 x 7
B = 42/42 - 35/42
B = 7/42
B = 7 x 1 / 7 x 6
B = 1/6

C = 12 * (1/3 - 1/6)
C = 12 x (1 x 2 / 3 x 2 - 1/6)
C = 12 x (2/6 - 1/6)
C = 12 x 1/6
C = 12 x 1
          6
C = 12/6
C = 6 x 2 / 6 x 1
C = 2/1
C = 2

D = 12 * 1/3 - 1/3 - 1/6
D = 12 x 1 - 1/3 - 1/6
          3
D = 12/3 - 1/3 - 1/6
D = 12 x 2 / 3 x 2 - 1 x 2 / 3 x 2 - 1/6
D = 24/6 - 2/6 - 1/6
D = 21/6
D = 3 x 7 / 3 x 2
D = 7/2

N° 2
A = 17/18 + 3 * 1/6
A = 17/18 + 3 x 1
                     6
A = 17/18 + 3/6
A = 17/18 + 3 x 3 / 6 x 3
A = 17/18 + 9/18
A = 26/18
A = 2 x 13 / 2 x 9
A = 13/9

B = 14/11 - 2/11 * 5
B = 14/11 - 2 x 5
                     11
B = 14/11 - 10/11
B = 4/11

C = 1 - (5/8 - 1/4)
C = 1 - (5/8 - 1 x 2 / 4 x 2)
C = 1 - (5/8 - 2/8)
C = 1 - 3/8
C = 1 x 8 / 1 x 8 - 3/8
C = 8/8 - 3/8
C = 5/8

D = 3/4 * 16/9 - 10/6 * 1/6
D = 3 x 16 - 10 x 1
       4 x 9     6 x 6
D = 48/36 - 10/36
D = 38/36
D = 2 x 19 / 2 x 18
D = 19/18

n° I
A = 3/7* (7/3-5/6) = 3/7  * ( 14/6 - 5/6) = 3/7 * 11/6 = 3*11/ 7*3*2 = 11/14
B = 3/7*7/3-5/6 = 21/21 - 5/6 = 6/6 - 5/6 = 1/6
C = 12* (1/3-1/6) = 12 * (2/6 - 1/6) = 12* 1/6 = 12/6 = 2
D =12*1/3 - 1/3 - 1/6 = 12/3 - 1/3 - 1/6 = 11/3 - 1/6 = 22/6 - 1/6 = 21/6 = 7*3/3*2 = 7/2

N° 2
A =17/18+3*1/6 = 17/18 + 3/6 = 17/18 + 9/18 = 26/18 = 2*13/2*9 = 13/9
B = 14/11 - 2/11*5 = 14/11 - 10/11 = 4/11
C = 1 - (5/8 - 1/4) = 1- (5/8 - 2/8) = 1 - 3/8 = 8/8 - 3/8 = 5/8
D = 3/4 * 16/9 - 10/6*1/6 = 3*4*4/4*3*3- 5*3/3*2*6 = 4/3 - 5/18 = 24/18 - 5/18 = 19/18