A= (1/2+7/8)×8/11 B=2-8/3×8/5 C=16/5 8/15 D= -7/-8 - 5/8×5

bonjour

a = ( 4/8 + 7/8) x 8/11
a = 11/8 * 8/11
a = 88/88 = 1

b = 2 - 64/15
b = 30/15 -64/15 = - 34/15

c = manque un signe

d = 7/8 - 25/8
d = - 8/8 = - 1