a) (5/6)^2 : 10/9 = 25/36 x 9/10 = 5/4 x 1/2 = 5/8
b) (1 si 4/5)^2 : (0,6)^2 = (5/5+4/5)^2 : (6/10)^2 = (9/5)^2 x (10/6)^2 = 81/25 x 100/36 = 9/1 x 4/4 = 9
c) 1/4 + 1/9 : (2/3)^2 = 1/4 + 1/9 x (3/2)^2 = 1/4 + 1/9 x 9/4 = 1/4 + 1/4 = 2/4 = 1/2
d) 0,(1) : 0,(3)^2 = 1/9 : (3/9)^2 = 1/9 : (1/3)^2 = 1/9 x 9/1 = 1
e) 2/3 - 1/3:1/2 = 2/3 - 1/3x2/1 = 2/3 - 2/3 = 0
f) (5/6-2/3)^2 : 0,(6)^2 = (5/6-4/6)^2 : (6/9)^2 = (1/6)^2 : (2/3)^2 = 1/36 : 4/9 = 1/36 x 9/4 = 1/4 x 1/4 = 1/16
