Réponses

2013-05-23T18:24:55+02:00

2/5 x 13/7 + 2/5 x (1/7 + 1/14) = 2x13/5x7 + 2/5x(2/14+1/14) = 26/35 + 2/5 x 3/14 = 26/35 + 6/70 = 52/70 + 6/70 = 58/70 = 29/35.

 

(10/8-1/4) x (7/12+2/3) = (10/8 - 2/8) x (7/12 + 8/12) = 8/8 x 15/12 = 1x15/12 = 15/12 = 3x5/3x4 = 5/4.

  • Utilisateur Brainly
2013-05-23T19:08:03+02:00

1) 2/5 x 13/7 + 2/5 x ( 1/7 + 1/14)

   =26/35+2/5*3/14

   =26/35+3/35

   =29/35

 

2) (10/8-1/4) x (7/12+2/3)

    =8/8*(7/12+8/12)

    =15/12

    =5/4