1/2 = 1*6 / 2*6 = 6/12

1/3 = 1*4 / 3*4 = 4/12

2/3 = 2*4 / 3*4 = 8/12

3/4 = 3*3 / 4*3 = 9/12

5/6 = 5*2 / 6*2 = 10/12

3/2 = 3*6 / 2*6 = 18/12