2/3:5/7=2/3*7/5=14/15
1/4:1/2=1/4*2/1=1/2
2/5:2/3=2/5*3/2=3/5
3/4:1/2=3/4*2/1=3/2= 1 1/2
3/7:3/5=3/7*5/3=5/7
4/9:8/9=4/9*9/8=4/8=1/2
1/2:3/5=1/2*5/3=5/6
2/3:4/5=2/3*5/4=5/6
5/6:7/12=5/6*12/7=10/7=1 3/7
2/3:5/7=2/3*7/5=14/15
1/4:1/2=1/4*2/1=1/2
2/5:2/3=2/5*3/2=3/5
3/4:1/2=3/4*2/1=3/2= 1 1/2
3/7:3/5=3/7*5/3=5/7
4/9:8/9=4/9*9/8=4/8=1/2
1/2:3/5=1/2*5/3=5/6
2/3:4/5=2/3*5/4=5/6
5/6:7/12=5/6*12/7=10/7=1 3/7