a) 2/3 + 0,6 = 2/3 + 3/5 = 10/15 + 9/15 = 19/15 = 1 4/15
b) 4,2 - 1 1/9 = 4 1/5 - 1 1/9 = 4 9/45 - 1 5/45 = 3 4/45
c) 3,6 - 1 1/2 = 3,6 - 1,5 = 2,1
d) 2 1/3 : 0,8 = 7/3 * 10/8 = 70/24 = 35/12 = 2 11/12
e) 5,2 - 2/7 = 5 1/5 - 2/7 = 5 7/35 - 10/35 = 4 7/35 + 25/35 =
= 4 32/35
f) 0,6 : 2/3 = 3/5 * 3/2 = 9/10
g) 2 3/20 + 1,27 = 3,15 + 1,27 = 4,42
h) 0,65 : 6,50 = 65 : 650 = 65/650 = 1/10
:)