用简便方法计算（小学五年级题目）

1.
0.4*2.67*2.5
=0.4*2.5*2.67
=1*2.67
=2.67

2.
47*0.125*8
=47*(0.125*8)
=47*1
=47

3.
5.9*9.9
=5.9*(10-0.1)
=5.9*10-5.9*0.1
=59-0.59
=58.41

4.
8.4*102
=8.4*(100+2)
=8.4*100+8.4*2
=840+16.8
=856.8

5.
0.02*26.9*50
=(0.02*50)*26.9
=1*26.9
=26.9

6.
3.54*6.5+2.73*6.5
=(3.54+2.73)*6.5
=6.27*6.5
=40.755

0.4*2.5*2.67=1*2.67=2.67
0.125*8*47=1*47=47
5.9*(1-0.1)=5.9-0.59=5.31
8.4*(100+2)=840+16.8=856.8
0.02*50*26.9=1*26.9=26.9
(3.54+2.73)*6.5=40.755

改变顺序或将数字拆开.
2.5x0.4x2.67=1x2.67=2.67
0.125x8x47=1x47=47
5.9x9.9=5.9x(10-0.1)=59-0.59=58.41
8.4x102=8.4x(100+2)=840+16.8=856.8
0.02x50x26.9=1x26.9=26.9
6.5x(3.54+2.73)=40.755

1.5.06*60+4.94*60
2.62.5*1000-61.5*1000
3.98.54*99+98.54
4.9.3*10-9.3*9
5.0.25*4+1.25*0.8
我就上五年级，这些绝对是五年级的题目，相信我我，绝对没问题

0.4乘2.5=1 1乘2.67=2.67
0.125乘8=1 1乘47=47

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