quelqu'un peut m'expliquer svp​

Bonjour,

Calculer:

A= 1/3-1/2+5/6

A= (1x2-1x3)/6+5/6

A= -1/6 + 5/6

A= -4/6

A= 2/3

B= 1- (1/3)+(1/9)-2/18

B= (18-6+2-2)/18

B= 12/18

B= 2/3

C= (2/5) x (5/3)+ (3/2) x 4

C= 2/3 + 12/2 barrer les 5, il reste 2/3

C= 2/3 + 6

C= (2 + 6x3)/3

C= 20/3

D= 1+3x(-2/7)+2x(-5/15)

D= (7-6)/7 - 10/15

D= 1/7 - 2/3

D= 3-14/ 21

D= -11/21

E= (1/3 - 1/2) / (1 + 5/3) - 2

E = (2/6 - 3/6) / (8/3) - 2

E = -1/6 / (8/3) - 2

E = -1/6 x 3/8 - 2

E = -3/48 - 2

E= -3/48 - 96/48

E= - 99/48

E= -33/16