1234501、“0 a02

0 a0=a3

0 a0=a4

0 aa=05

0

0 a0=060

0

0 0aa0=0700;5011

2

32

()345A12B

25

25

35

3567

|||1a+b=b+a2

a+b+c=a+(b+c) ++++3a-b-c=a-(b+c)1ab=ba2

a

b

c=a(b

c)3a+bc=ac+bc

(a

b)cacbca+bc (a

b)c=acbc =a

cbcacbc a

cbc=

a+bc =(a

b)ca99a a

ba=a

99+1 =a

b1a99 a 102=a

1001 =a

100+2=a

100a1 =a

100+a211

92

83

74

65

50

91

82

73

64

52106-26-74=106-26+74106-

26+74=106-26-743123+38-23=123-23+38 146-78+54=146+54-784

25

4125

8

125

80

25

4

125

856.27139=27913

abc=a(bc)1254100 125

810002 3 50+98+50 488+40+6050+50+98 488+40+60100+98 488+100198 5884 5 25×56×4 99× 125×825456 99125810056 9910005600 990006

65+28+35+7265+35+28+72100+100200725×125×4×8254125810010001000001 2 2540+4 135 1213522540+254 1351221000+100 135101100 13503

1 4

299×

256+256 45× 10299256+2561 45100+225699+1 45100+452256100 =4500+9025600 =45905

3 6

499×26 35× 8+35×6—4×35100126 358+6410026126 3510260026 3502574 5286535 528

89128 528

150+128=52865+35 =528

12889 =528

128150=528—100 =400

—89 =400

—150=428 =311 =250 3200÷25÷4=3200254=3200÷100=32 256—58+44 250÷

8×4=256+44—58 =250×

4÷8=300—58 =1000÷ 8=242 =125

+

3796+373+370.6+0.4-0.6+0.4 38

99+9912

101001000340.10.010.0015

106

107 16378

000126378

6301），7001），80001）。3637863780001）。49426

4

401[4]8

0

09

0

01000

0

0111

23412

10

100

1000

10

100

1000

13

1

1000 1

1000

1

1000 1

=10

1=101

=100 1

101001000

1

100 1

1001 =100 1

=10000

1

=10 1

=10 1

=100??

1=======2=======141

5253

54

4

85012

33145ABC

ABC6

6078910

1