a) 21,2 +1,56-20,4 = 22,76-20,4 = 2,36
b) -1,3 -15,64 +4,8 = - 16,94+4,8 = - 12,14
c) 1,5 -2,(3)-0,(6) =15/10- 21/90-6/9 = 135-21-60/90 = 54/90 = 3/5
d) 0,(3) -2,5 +7/6 = 3/9-25/10+7/6 = 1/3-5/2+7/6 = 2-15+7/6 = -6/6 = -1
e ) 4-1,(3)+1/6 = 4/1 - 12/9 + 1/6 = 4/1-4/3 +1/6 = 24-8+1/6 = 17/6
f -1,(3) -16/3 +6,(6) = -12/9-16/3 + 60/9 = 4/3- 16/3+20/3 = 0
