1/3 = (1*10)/(3*10) = 10/30
2/3 = (2*10)/(3*10) = 20/30
1/5 = (1*6)/(5*6) = 6/30
2/5 = (2*6)/(5*6) = 12/30
4/5 = (4*6)/(5*6) = 24/30
1/6 = (1*5)/(6*5) = 5/30
5/6 = (5*5)/(6*5) = 25/30
3/10 = (3*3)/(10*3) = 9/30
7/10 = (7*3)/(10*3) = 21/30
9/10 = (9*3)/(10*3) = 27/30