分数简便运算:
1、7/9+5/13+2/9+8/13
=(7/9+2/9)+(5/13+8/13)
=1+1
=2
2、24×(1/2-1/3+1/4-1/8)
=24×1/2-24×1/3+24×1/4-24×1/8
=12-8+6-3
=7
3、4/7+1/14-1/2
=8/14+1/14-7/14
=2/14
=1/7
4、5/3-3/8-5/8
=5/3-(3/8+5/8)
=5/3-1
=2/3
5、3/5+3/11+7/5+11
=(3/5+7/5)+11+3/11
=2+11+2/11
=13又2/11
6、3/4-{5/6-1/3}
=3/4-(5/6-2/6)
=3/4-1/2
=3/4-2/4
=1/4