Réponse :

bonjour

Explications étape par étape :

a 7/2+3/10

=7x5 / 2x5  + 3/10

=35/10 + 3/10

=38/10

b 5/6-5/36

=5x6/6x6  -5/36

=30/36 - 5/36

=25/36

c 3/7+6

=3/7 +6x7 /7

=3/7 +42/7

=45/7

d 48/55-1/5

=48/55 - 11x1 / 5x11

=48/55 - 11/55

=37/55

e 9-17/20

=9x20 /20 -17/20

=180/20 - 17/20

=163/20

f 15/56+9/7

=15/56 +9x8/7x8

=15/56 +72/56

=87/56