Réponses

Meilleure réponse !
2014-05-09T15:46:28+02:00
A = ( 1/8 + 7/12 ) x ( 6/5 : 4/15 )
A = (1 x 3 / 8 x 3 + 7 x 2 / 12 x 2) x (6/5 x 15/4)
A = (3/24 + 14/24) x (6 x 15)
                                   5 x 4
A = 17/24 x 90/20
A = 17 x 90
       24 x 20
A = 1530/480
A = 30 x 51 / 30 x 16
A = 51/16

B = 5/3 - 7/9
 
    1/4 - 1/2
B = 5 x 3 / 3 x 3 - 7/9
       1/4 - 1 x 2 / 2 x 2
B = 15/9 - 7/9
       1/4 - 2/4
B = 8/15  : -1/4
B = 8/15 x -4/1
B = - 32/15