求三个分数相加或相减,题越多越好.

3/8+7/10+5/8=17/10 7/8-(1/8+3/4)=0 4/7+1/6-4/7=1/6
2-7/9-2/9=1 3/5+7/8+2/5=15/8 7/9-(1/9+1/3)=1/3
1/4+(2/5+3/4)=7/5 5/6-3/10+1/6-7/10=0 3/4+1/6-2/3=1/4
7/8-1/4+4/9=77/72 1-1/3+2/7=20/21 1/2+4/5-3/10=1
5/6-(2/3-1/9)=5/18 9/10-(3/4+1/8)=1/40 1/2+2/3-3/4=5/12
7/8-1/6+1/4=23/24 1-(3/4-2/9)=17/36 9/10-1/5-1/2=1/5
1/4+3/7+1/2=33/28 7/8-(2/3+1/6)=1/24 1-(1/3+3/5)=1/15
1/2+1/4+1/3=13/12 7/8+1/4+1/2=5/8 5/7-(4/7+1/9)=2/63
1-1/4-1/2=1/4 3/4-1/6-1/3=1/4 3/10+1/4+2/5=19/20
2/3+1/6+1/12=11/12 1-1/4-2/5=7/20 1/2+1/9+1/12=25/36