aider moi svp ses urgenttt ses l'exos 54 est 56

Ex 54

A= 17/18 + 3x1/6 
A= 17/18 + 9/18
A= 27/18 
A = 3/2

B= 14/11 - 2/11x5
B= 14/11-10/11
B= 4/11

C= 1-(5/8 - 1/4)
C=1- ( 5/8-2/8)
C= 1-3/8
C= 8/8 - 3/8
C=5/8

D= ( 3/4 x16/9) -(10/6x1/6)
D= (3x4x4 / 4x3x3) - ( 2x5x1 / 2x18 )
D= 4/3 - 5/18
D= 24/18 - 5/18  
D= 19/18

exo 56 :

53/24 -(3/4+11/8) =
53/24-(6+11)/8 =
53/24 - 17/8 =
53/24 - 51/24 = 2/24 = 1/12

2(11/8)+53/24 =
22/8 + 53/24 = 119/24
66/24+53/24 =