12 2/15 -2 1/5 = 6(2/15 -1/5) =5 14/15
7 4/13 -6 3/26 = 1(4/13 -3/26) =1 5/26
10 10/13 -9/10 = 9 111/130
12 2/15 -2 1/5 = 6(2/15 -1/5) =5 14/15
7 4/13 -6 3/26 = 1(4/13 -3/26) =1 5/26
10 10/13 -9/10 = 9 111/130