Bonsoir, pouvez m'aider sur 3 exercices de calculs de fractions ? Je suis en 4ème. MERCI BEAUCOUP. S= -4/15+(2+7/-30) U=7/4-(-1/8-3/10) W=3/4-(-5/12-1/3)+(-2-1/

Bonsoir,

S= -4/15+(2+7/-30)

S = (- 4 x 2) / (15 x 2) + [(2 x 30) / (1 x 30) - 7/30]

S = - 8/30 + (60/30 - 7/30)

S = - 8/30 + 53/30

S = 45/30

S = (15 x 3) / (15 x 2)

S = 3/2

U=7/4-(-1/8-3/10)

U = (7 x 10) / (4 x 10) - [(- 1 x 5) / (8 x 5) - (3 x 4) / (10 x 4)]

U = 70/40 - (- 5/40 - 12/40)

U = 70/40 - (- 17/40)

U = 87/40

W=3/4-(-5/12-1/3)+(-2-1/6)

W = (3 x 3) / (4 x 3) - [- 5/12 - (1 x 4) / (3 x 4)] + [(- 2 x 12) / (1 x 12) - (1 x 2) / 6 x 2)]

W = 9/12 - (- 5/12 - 4/12) + (- 24/22 - 2/12)

W = 9/12 + 9/12 - 26/12

W = - 8/12

W = (4 x - 2) / (4 x 3)

W = - 2/3.

Hello !

S = -4/15+(2+7/-30)

S = -4/15 + (60/30-7/30) = -4/15 + 53/30

S = -8/30 + 53/30 = 45/30 = 3/2

U = 7/4-(-1/8-3/10)

U = 7/4-(-5/40-12/40) = 7/4-(-17/40)

U = 7/4 + 17/40 = 70/40 + 17/40 = 87/40

W = 3/4-(-5/12-1/3)+(-2-1/6)

W = 3/4-(-5/12-4/12)+(-12/6-1/6)

W = 3/4-(-9/12)-13/6 = 3/4+3/4-13/6

W = 6/4-13/6 = 36/24-52/24 = -16/24 = -2/3

Bonne soirée