Réponses

2014-09-14T14:18:30+02:00
13-5+4
=8+4
=4

17-8+9
=9+9
=18

3.5-1.2+2.2
=2.3+2.2
=0.1

5-1.6+2.7
=4.6-2.7
=1.9
mais tu n'a pas fais les autres ?
13-(5+4)
=13-9
=4

17-(8+9)
=17-17
=0

3.5-(1.2+2.2)
=3.5-3.4
=0.1

5-(1.6+2.7)
=5-4.3
=0.7