Sagot :
bonjour
7/9 + 11 /15 = 35/45 + 33/45 = 68/45
7/8 + 22 /12 = 7/8 + 11/6 = 21/24 + 44/24 = 65/24
6/5 + 3 /8 = 48/40 + 15/40 = 63/40
15/18 - 5 /27 = 5 /6 - 5 /27 = 45/54 - 10/54 = - 35/54
Réponse:
a) 7/9 + 11/15 = 7x15/9x15 + 11x9/15x9
= 105/135 + 99/135
= 105+99/135
= 204/135
= 68/45
b) 7/8 + 22/12 = 7x3/8x3 + 22x2/12x2
= 21/24 + 44/24
= 21+44/24
= 65/24
c) 6/5 + 3/8 = 6x8/5x8 + 3x5/8x5
= 48/40 + 15/40
= 48+15/40
= 63/40
d) 15/18 - 5/27 = 15x3/18x3 - 5x2/27x2
= 45/54 - 10/54
= 45-10/54
= 35/54