2). a =5 / 7 + 2 / 7 = 7 / 7
b = 1 / 3 + 2 / 3 = 3 /3
c = 7 / 10 +3 /10 = 10 / 10
d = 2 / 6+ 4 / 6 = 6/6
3) . a = 7 / 7
b = 50 /100
c = 11 /10
d = 10 /9
e = 90 /100
c si d = fractii supraunitare
4). 9 / 10 = 1 / 10 + 8 / 10
9 /10 = 2 / 10 + 7 /10
9 /10 = 3 /10 + 6 /10
9 /10 = 4 /10 + 5 /10
25 /100 = 1 / 100 + 24 /100
25 /100 = 2 /100 + 23 /100
25 /100 = 3 /100 + 22 /100
25 /100 = 4 /100 + 21 /100
25 /100 = 5 / 100 + 20 /100
