Răspuns:
Produsul mezilor = produsul extremilor
A.
1/4 = 3/12
2/5 = 10/25
3/8 = 15/40
B.
3/4 = 12/16
4/5 = 12/15
6/8 = 12/16
C.
16/24 = 4/6
18/24 = 3/4
20/24 = 10/12
D.
15/20 = 3/4
8/20 = 2/5
9/24 = 3/8
