Réponses

2014-01-16T17:59:27+01:00
  • Utilisateur Brainly
2014-01-16T18:00:52+01:00
3/5 + 1/15 = 3x3/5x3 + 1/15 = 15 = 9/15 + 1/15 = 10/15
25/8 + 2.5/4 = 25/8 + 2.5x2/2x4 = 25/8 + 5/8 = 30/8 
21/9 - 1/3 = 21/9 - 1x3/3x3 = 21/9 - 3/9 = 24/9
25/3 -64/12 = 25x4/3x4 - 64/12 = 100/12 - 64/12 = 36/12 = 3