Mathématiques

Question

URGENT qui peut m'aider svp ?
URGENT qui peut m'aider svp ?

1 Réponse

  • Bonsoir,

    53)

    a) 3/3 - 2/3 = 1/3
    Il restait au primeur 1/3 de ses salades à midi

    b) 1/3 x 7/8 = 7/24 
    Le primeur a vendu 7/24 de des salades l'après midi

    54)

    A = 5 x 2/3 - 1/3
    A = 10/3 - 1/3
    A = 9/3

    B = 7/4 - 3/4 x 3/2
    B = 7/4 - 9/8
    B = 7 x 2 / 4 x 2 - 9/8
    B = 14/8 - 9/8
    B = 5/8

    C = (5/6 + 7/12) x 3/5
    C = (5 x 2 / 6  x 2 + 7/12) x 3/5
    C = (10/12 + 7/12) x 3/5
    C = 17/12 x 3/5
    C = 51/60
    C = 3 x 17 / 3 x 20
    C = 17/20

    D = 3/4 x 2/9 + 28/15 x 25/14
    D = 6/36 + 700/210
    D = 6/36 + 70/21
    D = 6 x 21 / 36 x 21 + 70 x 36 / 21 x 36
    D = 126/756 + 2520/756
    D = 2646/756
    D = 378 x 7 / 378 x 2
    D = 7/2

    E = (1/3 x 6/5 - 3/10) x 15/4
    E = (6/15 - 3/10) x 15/4
    E = (6 x 2 / 15 x 2 - 3 x 3 / 10 x 3) x 15/4
    E = (12/30 - 9/30) x 15/4
    E = 3/30 x 15/4
    E = 45/120
    E = 15 x 3 / 15 x 8
    E = 3/8

    F = 8 + 2 x 3 x 6
          7 + 2    5 x 3
    F = 10/9 x 18/15
    F = 180/135
    F = 45 x 4 / 45 x 3
    F = 4/3