Réponse :

bonjour

Explications étape par étape :

A=15/23+49/23

=64/23

B=250/18+128/18

=378/18

=21

C=35/9+29/27

=35*3/9*3 +29/27

=105/27+29/27

=134/27

D=3/11+38/5

=3*5/11*5 +38*11/5*11

=15/55+418/55

=433/55

E=4/35-19/35

=-15/35

=3/5

F=256/5-64/5

=192/5

G=102/3+48/15

=34+16/5

=34*5/5+16/5

==170/5+16/5

=186/5

H=7/4-5/3

=7*3/4*3 -5*4/4*3

=21/12-20/12

=1/12