1、 34×3.535-3.5×34.34
=34×3.5×1.01-3.5×34×1.01
=0
2、8+89+899+8999+89999
=9+90+900+9000+90000-5
=99999-5
=99994
3、0.67×2.1+0.018×21+8.5×0.79
=0.67×2.1+0.18×2.1+8.5×0.79
=（0.67+0.18）×2.1+8.5×0.79
=0.85×2.1+0.85×7.9
=0.85×（2.1+7.9）
=0.85×10
=8.5
4、22222.2×9.99999
=22222.2×（10-0.00001）
=222222-0.222222
=222221.777778
5、1997×19961996-1996×19971997
=1997×1996×10001-1996×1997×10001
=0
6、0.02+0.04+0.06+0.08+……+19.94+19.96+19.98
=（0.02+19.98）×999÷2
=10×999
=9990
7、99999×77778+33333×66666
=99999×77778+99999×22222
=99999×（77778+22222）
=99999×100000
=9999900000
8、（4又5/6-3又3/4）/（3/14+2/7）
=13/12÷1/2
=13/6
=2又1/6
9、（4.8/1又4/5+3又1/2+7又1/3）*4/9
=（2又2/3+7又1/3+3.5）*4/9
=（10+3.5）*4/9
=13.5*4/9
=6
10、17.2/【（3又2/5-1.25）*2/3】
=17.2/【2.15*2/3】
=17.2÷43/3
=1.2
11、5*5又1/5
=5*5+5*1/5
=25+1
=26
12、（5又2/5-1.8）/[（1.15+13/20）*1又2/3]
=3.6/[1.8*5/3]
=3.6/3
=1.2
13、3又5/8*5又1/5+5又1/5*6又3/8
=5.2*(3又5/8+6又3/8）
=5.2*10
=52
14、[3/4-7/8/(5/6+4/5)]*28
=[3/4-7/8÷49/30]*28
=[3/4-15/28]*28
=3/4*28-15/28*28
=21-15
=6
15、(1.25*4/5-0.76)/(1又3/8+1又1/40）
=(1-0.76)/2.4
=0.24/2.4
=0.1
16、[(0.2+1/3)*4.5]/(8又1/20-6.45）
=8/15*4.5/1.6
=2.4/1.6
=1.5
17、8.16-1.26/0.3*1.5
=8.16-4.2*1.5
=8.16-6.3
=1.86
18、8.4*[(1.2+3又1/3）/3.4-1/2]
=8.4*[68/16/3.4-1/2]
=8.4*[5/4-1/2]
=8.4*3/4
=6.3
19、19.38-4又7/8-5又1/8
=1.938-(4又7/8+5又1/8）
=19.38-10
=9.38
20、13又7/13-（6又3/5+3又7/13）
=13又7/13-3又7/13-6又3/5
=10-6又3/5
=3.4
21、1又3/4+[2又3/14-（2又3/14-1.875）]/2又1/12
=1又3/4-15/8*12/25
=1又3/4-9/10
=0.85
22、（9.4-8又2/5）/[（1.1+1/15）*1又7/18]
=1/[7/6*25/18]
=1÷175/108
=108/175
