bonjour
- 5/12 + 8/3 = - 5/12 + 32/12 = 27 /12 = 9 /4
11/14 + 7/4 = 22/28 + 49/28 = 71/28
- 2/7 - 4/3 = - 6/21 - 28/21 = - 34 /21
