Réponses

2014-09-14T12:30:27+02:00
Calculer à la main et donner le résultat sous forme d'une fraction irréductible :

A: (2|5+1|3) ÷ 2|3
A = (2 x 3 / 5 x 3 + 1 x 5 / 3 x 5) : 2/3
A = (6/15 + 5/15) : 2/3
A = 11/15 x 3/2
A = 33/30
A = 3 x 11 / 3 x 10
A = 11/10

B: 16|15 ÷ 2|9 - 2|3
B = 16/15 x 9/2 - 2/3
B = 144/30 - 2/3
B = 144/30 - 2 x 10 / 3 x 10
B = 144/30 - 10/30
B = 134/30
B = 2 x 67 / 2 x 15
B = 67/15

C: 2|13 - 5|13 ÷ 10|16
C = 2/13 - 5/13 x 16/10
C = 2/13 - 80/130
C = 2 x 10 / 13 x 10 - 80/130
C = 20/130 - 80/130
C = - 60/130
C = 10 x - 6 / 10 x 13
C = - 6/13