Exprimer sous forme fractionnaire simplifier ou de nombre entier : a) 5/4 x 1/3 - 5/6 x 1/2 b) 5/4 x (1/3 - 5/6 ) x 1/2 c) 5/4 x ( 5/3 - 2/9 )

A = 5/4 X 1/3 -5/6 X 1/2
5/12 -5/12 = 0

B = 5/4 X (1/3 -5/6) X 1/2
5/4 ( 2/6 -5/6) X 1/2
5/4 X -3/6 X 1/2
-15/24 X 1/2
-15/48 = -5/16

C = 5/4 X (5/3 -2/9)
5/4 X ( 10/9 -2/9)
5/4 X 8/9
40/36 = 10/9

D = 5/4 X 5/3 -2/9
25/12 -2/9
225/108 - 24/108 = 201/108 = 67/36

E = 3/7 +4/7 X 5/2
3/7 +20/14
6/14 +20/14 = 26/14 = 13/7

F = (3/7 +4/7) X 5/2
7/7 X 5/2
35/14 = 5/2

a) 5/4 x 1/3= - 5/6 x 1/2= 5x1 / 4x3 - 5x1 / 6x2 = 5/12 - 5/12 =0/12
b) 5/4 x(1/3 - 5/6 ) x1/2 = 5/4 x (1x6/3x6 -3x5/6x3 ) x 1/2 = 5/4x (6/18-15/18)x1/2
=1/2 x (-3/18) x 1/2 = (-3/72) =-3:3/72:3 =1/24