Bonjour
A = 3/5 - 3/5 : 12/7
A = 3/5 - 3/5 x 7/12
A = (3 x 12) / (5 x 12) - 21/60
A = 36/60 - 21/60
A = 15/60
A = (15 x 1) / (15 x 4)
A = 1/4
B = (4/5 x 35/16) : (1/4 - 5/6)
B = 140/80 : [(1 x 3) / (4 x 3) - (5 x 2) / (6 x 2)]
B = (20 x 7) / (20 x 4) : (3/12 - 10/12)
B = 7/4 : (- 9/12)
B = 7/4 : (3 x - 3) / (3 x 4)
B = 7/4 : - 3/4
B = 7/4 x - 4/3
B = - 28/12
B = (4 x - 7) / (4 x 3)
B = - 7/3
C = (1 + 5/6) : (1/3 - 2)
C = [(1 x 6) / (1 x 6) + 5/6] : [1/3 - (2 x 3) / (1 x 3)]
C = (6/6 + 5/6) : (1/3 - 6/3)
C = 11/6 : (- 5/3)
C = 11/6 x (- 3/5)
C = - 33/30
C = (3 x - 11) / (3 x 10)
C = - 11/10.
