Bonsoir
A = 5/2 x -7/3
A = (-5 x 7)/(2 x 3)
A = -35/6
B = -7 x 8/5
B = (-7 x 8)/5
B = -56/5
C = -3/7 x 14/-5
C = 14/7 x 3/5
C = (2 x 7)/7 x 3/5
C = 2 x 3/5
C = 6/5
D = 7/6 - (-1/2 + 1/3)
D = 7/6 - (-3/6 + 2/6)
D = 7/6 - (-1/6)
D = 7/6 + 1/6
D = 8/6
D = (2 x 4)/(2 x 3)
D = 4/3
E = 1 - 3/4 x 2/3
E = 1 - 3/3 x 2/4
E = 1 - 2/(2 x 2)
E = 2/2 - 1/2
E = 1/2
F = 5/3 x (2/3 + 1/5)
F = 5/3 x (10/15 + 3/15)
F = 5/3 x 13/15
F = 5/15 x 13/3
F = 5/(3 x 5) x 13/3
F = 1/3 x 13/3
F = 13/9
G : Clément mange la moitié du tiers de 600g
600 x 1/3 = 600/3 = (3 x 200)/3 = 200
200/2 = 100 g
H : Damien mange 1/5. Émeline mange 1/3 du reste
Il reste : 1 - 1/5 = 5/5 - 1/5 = 4/5
4/5 x 1/3 = 4/15
I : les 7/21 des 9 km dun cross
9 x 7/21 = 9 x 7/(7 x 3) = 9 x 1/3 = (3 x 3)/3 = 3 km
J = 1/3 x 4/5 + 3/10 x 6
J = 4/15 + 6/10 x 3
J = 4/15 + (2 x 3)/(2 x 5) x 3
J = 4/15 + 3/5 x 3
J = 4/15 + 9/5
J = 4/15 + 27/15
J = 31/15
