Bonjour je n'arrive pas a faire cette exercice de maths : Calculer et simplifier la fraction obtenue a. 2/7 + 4/9 b. 3/8-5/3 c. -4/5-7/9 d. 1+2/9 e. 1-7/3 f. 3+

Bonjour,

Calculer et simplifier la fraction obtenue

a. 2/7 + 4/9

= (2 x 9) / (7 x 9) + (4 x 7) / (9 x 7)

= 18/63 + 28/63

= 46/63

b. 3/8-5/3

= (3 x 3) / (8 x 3) - (5 x 8) / (3 x 8)

= 9/24 - 40/24

= - 31/24

c. -4/5-7/9

= (9 x - 4) / (9 x 5) - (7 x 5) / (9 x 5)

= - 36/45 - 35/45

= - 71/45

d. 1+2/9

= (1 x 9) / (1 x 9) + 2/9

= 9/9 + 2/9

= 11/9

e. 1-7/3

= (1 x 3) / (1 x 3) - 7/3

= 3/3 - 7/3

= - 4/3

f. 3+3/4

= (3 x 4) / (1 x 4) + 3/4

= 12/4 + 3/4

= 15/4.

Bonjour,

A=2/7+4/9

A=18/63+28/63

A=46/63

B=3/8-5/3

B=9/24-40/24

B=-31/24

C=-4/5-7/9

C=-36/45-35/45

C=-71/45

D=1+2/9

D=9/9+2/9

D=11/9

E=1-7/3

E=3/3-7/3

E=-4/3

F=3+3/4

F=12/4+3/4

F=15/4