1/2+1/2=
1/2(2/5)
1/2+2/3
4/5+1/5+6/5
1/2+2/3+4/5=
2/5(2/3)
1/3+2/3+/4/3
2/3-1/4
(2/3)/(1/2)
1/2-7/2
4/3
11/5
4/15
7/6
-6/2
1
59/30
5/12
1/5
7/3
