Répondre :
A:26/21-6/3x2/7
=26/21-12/21
=14/21
=2/3
b:3-3x5/12
=3-15/12
=36/12-15/12
=21/12
=7/4
c:(7/3+1/4)x3/62
=(28/12+3/12)x3/62
=31/12x3/62
=3/24
=1/8
=26/21-12/21
=14/21
=2/3
b:3-3x5/12
=3-15/12
=36/12-15/12
=21/12
=7/4
c:(7/3+1/4)x3/62
=(28/12+3/12)x3/62
=31/12x3/62
=3/24
=1/8