Réponse :
Explications étape par étape :
a) 3/7 ÷ 4/5 = 3/7 × 5/4 = 15/28
b) 6/11 ÷ 5/4 = 6/11 × 4/5 = 24/55
c) 11/9 ÷ 1/2 = 11/9 × 2/1 = 22/9
d) 15/4 ÷ 2 = 15/4 × 1/2 = 15/8 = 1,875
e) 4 ÷ 7/9 = 4 × 9/7 = 36/7
f) 3/8 ÷ 5/7 = 3/8 ×7/5 = 21/40 = 0,525
