Répondre :
= 1 : 4/7
= 1 x 7/4
= 7/4
= 1 : (-3/5)
= 1 x ( -5/3)
= -5/3
= 1 : (-2/11)
= 1 x (-11/2)
= -11/2
= 1 x 7/4
= 7/4
= 1 : (-3/5)
= 1 x ( -5/3)
= -5/3
= 1 : (-2/11)
= 1 x (-11/2)
= -11/2