Réponse :
Explications étape par étape
Bonsoir
1/12 + 7/15
= (1 x 5)/(12 x 5) + (7 x 4)/(15 x 4)
= 5/60 + 28/60
= 33/60
= (3 x 11)/(3 x 20)
= 11/20
33/6 - 22/9
= (33 x 3)/(6 x 3) - (22 x 2)/(9 x 2)
= 99/18 - 44/18
= 55/18
11/30 + 11/25
= (11 x 5)/(30 x 5) + (11 x 6)/(25 x 6)
= 55/150 + 66/150
= 121/150
