Réponses

2013-04-28T16:09:47+02:00

A= 3/8

B=79/12

C=65/24

 

Addictionne tout sa et regarde si tu trouve bien un entier :)

2013-04-28T16:14:59+02:00
A = 1 - (3/8 + 1/4)
A = 8/8 - (3/8 + 2/8)
A = 8/8 - 5/8
A = 3/8

B = 7 - 5/3 x 1/4
B = 7 - 5x1/3x4
B = 7 - 5/12
B = 84/12 - 5/12
B = 79/12

C = 5/2 x 1/6 x 13/2
C = 5x1/2x6 x 13/2
C = 5/12 x 13/2
C = 5x13/12x2
C = 65/24

A+B+C = 3/8 + 79/12 + 65/24
A+B+C = 9/24 + 158/24 + 65/24
A+B+C = 232/24 = 116/12 = 29/3