Réponses

2014-02-20T18:48:41+01:00
A) 1/4 + 3/2 x 5/12 = 1/4 + 15/24 = 1 x 6 / 4 x 6 + 15/24 = 6/24 + 15/24 = 21/24

b) (1+1/2) : 1/4 - 3  = (1 x 2 / 1 x 2 + 1/2) : 1/4 - 3 = (2/2 + 1/2) : 1/4 - 3 = 3/2 : 1/4 - 3 = 3/2 x 4/1 - 3 = 12/2 - 3 = 12 x 3 / 2 x 3 - 3 x 6 / 1 x 6 = 36/6 -18/6 = 18/6 = 6 x 3 / 6 x 1 = 3/1 = 3