Réponses

2012-11-22T20:31:42+01:00

A 5/7 +3/4 = 20/28/21/28 = 41/28

C/ 11/7 : 21/4 = 11*4/7*21 = 44/14

B /( 4+3)/4 : (15-1)/3

= 7/4 : 14/3 = 7*3/14*4 = 21/56

 

2012-11-22T20:38:54+01:00

A) 5/7 + 3/4 = 20/28 + 21/28 = 41/28

B)( 1+3)/4 : (5-1)/3

= 4/4 : 4/3 = 4*3/4*4 = 12/12 = 1

C) 11/7 : 21/4 = 11*4/7*21 = 44/14 = 22/7