Réponse :
Bsr
Explications étape par étape :
A = 5/4 * (5/3 - 2/9)
A = 5/4 * (15/3 - 2/9)
A = 5/4 * 13/9
A = 65/36
B = 5/4 * 5/3 - 2/9
B = 25/12 - 2/9
B = 75/36 - 8/36
B = 67/36
C = 7 : (2/5 - 1)
C = 7 : (2/5 - 5/5)
C = 7 : (-3/5)
C = 7 * (-5/3)
C = - 35/3