B=(1/6+1/4):-5/4 ——————— A= 2/4 - 3/7 x 14/9 B= - 7/8x(2/3-1) C= 4/5 x 1/4 x 2/5 Merci d’avance

Bonsoir,

B=(1/6+1/4)/(-5/4 )

(2/12 + 3/12) /(-5/4)

= (5/12)/ -5/4

=5/12 *-4/5

= -20/ 60 = - 2/6 = -1/3

A= 2/4 - 3/7 x 14/9

2/4 - 42/63

= 2/4 - 2/3  

= 6/12 - 8/12

= -2/12= -1/6

B= - 7/8x(2/3-1)

2/3 - 1 = 2/3 - 3/3 = -1/3

7/8 * -1/3 = -7/24

C= 4/5 x 1/4 x 2/5

4/20 * 2/5

= 8/100= 4/50 = 2/25