2/3+2/6= 3/4+1/3= 1/5+2/4= 3/4-1/4= 4/6-1/2=

1. 2/3 + 2/6 = 4/6 + 2/6 = 6/6 = 1
2. 3/4 + 1/3 = 9/12 + 4/12 = 13/12 = 1 1/12
3. 1/5 + 2/4 = 4/20 + 10/20 = 14/20 = 7/10
4. 3/4 - 1/4 =2/4 = 1/2
5. 4/6 - 1/2 = 4/6 - 3/6 = 1/6

2/3+2/6= 4/6+2/6= 6/6= 1

3/4+1/3= 9/12+4/12= 13/12= 1 1/2

1/5+2/4= 4/20+10/20= 14/20= 7/10

3/4-1/4= 2/4= 1/2

4/6-1/2= 4/6-3/6= 1/6