a) 2,2+ 1 1/4= 2 2/10 + 1 1/4 =2 1/5 + 1 1/4 = 11/5 + 5/4 = 44/20+ 25/20 = 69/20 = =3 9/20
b)6 2/3 - 3,125= 6 2/3 - 3 125/1000 = 20/3 - 3 1/8 = 20/3 - 25/8 = 160/24 - 75/24 = 85/24 = 3 13/24
c)4,50 - 2 1/2 + 3 1/3= 4 5/10 - 2 1/2 + 3 1/3 = 4 1/2 - 5/2 + 10/3 = 9/2 - 5/2 + 10/3 = 4/2 + 10/3 = 2 + 10/3 = 6/3 + 10/3 = 16/3 = 5 1/3