3/4 - 1/8
1/5 + 1/6
4/15+2/5
7/10 - 1/2
1/3 - 1/4

3/4-1/8=6/8-1/8=5/81/5+1/6=6/30+5/30=11/304/15+2/5=4/15+6/15=10/15=2/37/10-1/2=7/10-5/10=2/10=1/51/3-1/4=4/12-3/12=1/12