1、1.25×(8+10)
=1.25×8+1.25×10
=10+12.5
=22.5
2、1.24+0.78+8.76
=(1.24+8.76)+0.78
=10+0.78
=10.78
3、1/2-(4/5-1/2)
=1/2+1/2-4/5
=1-4/5
=1/5
4、4800÷25÷4
=4800÷(25x4)
=4800÷100
=48
5、2/5-(3/8-3/5)
=2/5+3/5-3/8
=1-3/8
=5/8
6、3/4-(3/7-1/4)
=3/4+1/4-3/7
=1-3/7
=4/7
7、3.2x0.125x2.5
=0.125x8x(0.4x2.5)
=1x1
=1
8、0.4×125×25×0.8
=(0.4×25)×(125×0.8)
=10×100
=1000
9、1.25×(8+10)
10、9123-(123+8.8)
=9123-123-8.8
=9000-8.8
=8991.2
1.6÷ 3/8 – 3/8 ÷6
=1/6x(3/8-3/8)
=1/6x0
=0
2.4/7 × 5/9 + 3/7 × 5/9
=(4/7+3/7)x5/9
=1x5/9
=5/9
3.5/2 -（ 3/2 + 4/5 ）
=5/2-3/2-4/5
4.6 ×（ 1/2 + 2/3 ）
=6x1/2+6x2/3
=3+4
=7
5.8 × 4/5 + 8 × 11/5
=8x(4/5+11/5)
=8x3
=24
6.31 × 5/6 – 5/6
=(31-1)x5/6
=30x5/6
=25
7.4/5 × 25/16 + 2/3 × 3/4
=5/4+1/2
=5/4+2/4
=7/4
8.101 × 1/5 – 1/5 × 21
=(101-21)x1/5
=80x1/5
=16
1. 0.4×125×25×0.8 =（0.4×25）×（125×0.8）=10×100=1000
2. 1.25×（8+10）=1.25×8+1.25×10 =10+12.5=22.5
3.9123-（123+8.8）=9123-123-8.8=9000-8.8=8991.2
4.1.24×8.3+8.3×1.76 =8.3×（1.24+1.76） =8.3×3=24.9
5.9999×1001=9999×（1000+1）=9999×1000+9999×1=10008999
6. 14.8×6.3-6.3×6.5＋8.3×3.7=（14.8-6.5）×6.3＋8.3×3.7=8.3×6.3+8.3×3.7=8.3×（6.3＋3.7）=8.3×10=83
7. 1.24+0.78+8.76=（1.24+8.76）+0.78=10+0.78=10.78
8. 933-157-43 =933-（157+43） =933-200 =733
9. 4821-998=4821-1000+22=3823
10. 32×125×25=4×8×125×25=（4×25）×（8×125）=100×1000=100000 9048÷26=（2600+2600+2600+1248）÷26=2600÷26+2600÷26+2600÷26+1248÷26=100+100+100+48=348
11. 2881÷ 43=（1290+1591）÷ 43=1290÷43+1591÷43=30+37 =67 3.2×42.3×3.75-12.5×0.423×16=3.2×42.3×3.75-1.25×42.3×1.6=42.3×(3.2×3.75-1.25×1.6)=42.3×(4×0.8×3.75-1.25×4×0.4)=42.3×(4×0.4×2×3.75-1.25×4×0.4)=42.3×(4x0.4x7.5-1.25x4x0.4)=42.3×[4×0.4×(7.5-1.25)]=42.3×[4×0.4×6.25]=42.3×(4×2.5) =423
12. 1.8+18÷1.5-0.5×0.3 =1.8+12-0.15=13.8-0.15 =13.65
13. 6.5×8+3.5×8-47 =52+28-47 =80-47 =33 (80-9.8)×5分之2-1.32 =70.2X2/5-1.32=28.08-1.32 =26.76
14. 8×7分之4÷[1÷(3.2-2.95)] =8×4/7÷[1÷0.25]=8×4/7÷4 =8/7
15. 2700×（506－499）÷900 =2700×7÷900 =18900÷900 =21
16. 33.02－（148.4－90.85）÷2.5=33.02－57.55÷2.3=33.02－23.02=10
17. （1÷1－1）÷5.1 =（1－1）÷5.1 =0÷5.1 =0
18. 18.1＋（3－0.299÷0.23）×1=18.1＋1.7×1 =18.1＋1.7 =19.8
19. 9000÷72×(1.25×0.7×8)=9000÷72×7=125×7=875
20. 61-(1.25+2.5×0.7)=61-3=58
21. [(10-0.8)+9.85]-2÷0.125=19.05-2÷0.125=19.05-16=13.05
22. 5.4÷1.8+240×1.5=3+360=363
23. 9000÷72×(1.25×0.7×8）=9000÷72×7=125×7=875
24. 61-(1.25+2.5×0.7)=61-3=58
25. [(10-0.8)+9.85]-2÷0.125=19.05-2÷0.125=19.05-16=3.05
26. 408－12×24= 408 - 288= 120
27. （46＋28）×60= 74 x 60= 4440
28. 42×50－17 = 2100- 17 = 2083
29. 32＋105÷5 = 32 + 21= 53
30. 420×（327－238） = 420 x 89 = 37380
31. (4121+2389)÷7 = 6510 ÷7 = 930
32. 3.416÷（0.016×35） = 3.416 ÷0.56 = 6.1
33. 0.8×[(10－6.76)÷1.2] = 0.8 x(3.24÷1.2) = 0.8 x 2.7 = 2.16
34. 5.67×0.2-0.62 = 1.134-0.62 = 0.514
35.0.4×0.7×0.25 = 0.4 x 0.2 5 x 0.7 = 0.1 x 0.7 = 0.07
36. 0.78+5.436+1 = 6.216 +1 = 7.216
37. 30.8÷[14－(9.85＋1.07)] = 30.8 ÷ (14 - 10.92) = 30.8÷3.08 = 10
38. [60－(9.5＋28.9)]÷0.18 = (60- 38.4)÷0.18 = 21.6 ÷0.18 = 120
39. 2.881÷0.43－0.24×3.5 = 6.7 - 0.24 x3.5 = 6.7 - 0.84 = 5.86
40. 20×[(2.44－1.8)÷0.4＋0.15] = 20x (0.64 ÷0.4 +0.15)= 20x(1.6 +0.15) = 20 x1.75 = 35
41. 28-(3.4+1.25×2.4) = 28 - (3.4 + 3) = 28 - 6.4 = 21.6
42. 2.55×7.1+2.45×7.1 = (2.55 + 2.45) x7.1 = 5 x7.1=35.5
43. 0.8×〔15.5-(3.21+5.79)〕 = 0.8 x (15.5 - 9) = 0.8 x 6.5 = 5.2
44.（31.8+3.2×4）÷5 = (31.8 + 12.8)÷5 = 44.6÷5 = 8.92
45. 31.5×4÷(6+3) = 126 ÷ 9 = 14
46. 2÷2.5+2.5÷2 = 0.8 + 1.25 =2.05
47. 194－64.8÷1.8×0.9 = 194 -36 x0.9 = 194-32.4 = 161.65180－705×6 = 5180 - 4230=950
48. 24÷2.4－2.5×0.8 =10 -2=8
49. 405×(3213-3189) =405x24 = 9720
59. 125×(97-81) =125x16 =2000
60. 6942+480÷3 = 6942 + 160 = 6782
61. 20+80÷4-20 = 20 + 20 -20 = 40 -20 = 20
62. 100÷（32-30）×0 = 100 ÷2 x0= 50 x0 = 0
63. 25×4-12×5 = 100 - 60 = 40
64. 70×〔（42-42）÷18〕=70 x (0÷18) = 70x0 = 0
65. 75×65+75×35 = 75 x (65 +35) = 75x100 = 7500
66. 6-1.6÷4= 6- 0.4 = 5.6
67. 5.38+7.85-5.37= 13.23 - 5.37=7.86
68. 7.2÷0.8-1.2×5=9 - 6 =3
69. 6-1.19×3-0.43= 6-3.57 - 0.43 = 6- (3.57 + 0.43) = 6-4 = 2
70. 6.5×（4.8-1.2×4）= 6.5 x(4.8 - 4.8 )=6.5 x0 = 0
71. 0.68×1.9+0.32×1.9 = (0.68 + 0.32) x1.9 = 1 x 1.9 = 1.9
72. 10.15-10.75×0.4-5.7 = 10.15 - 4.3 - 5.7 = 10.15 -(4.3 + 5.7)=10.15 - 10 =0.15
73. 5.8×（3.87-0.13）+4.2×3.74 = 5.8 x 3.74 +4.2 x 3.74 = (5.8 +4.2)x3.74 = 10 x 3.74 = 37.4
74. 32.52-（6+9.728÷3.2）×2.5 = 32.52 - (6+3.04)x2.5 = 32.52 - 9.02 x 2.5 = 32.52 -22.55 = 9.97
75.（136+64）×（65-345÷23）= 200x(65-15) = 200x 50=10000
76. 0.4×125×25×0.8 =(0.4×25)×(125×0.8)=10×100=1000
77. 1.25×(8+10) =1.25×8+1.25×10=10+12.5=22.5
78. 9123-(123+8.8) =9123-123-8.8=9000-8.8=8991.2
79. 1.24×8.3+8.3×1.76 =8.3×(1.24+1.76)=8.3×3=24.9
80. 9999×1001 =9999×(1000+1)=9999×1000+9999×1 =10008999
81. 14.8×6.3-6.3×6.5+8.3×3.7 =(14.8-6.5)×6.3+8.3×3.7=8.3×6.3+8.3×3.7
82. 8.3×(6.3+3.7) =8.3×10 =83
83. 1.24+0.78+8.76 =(1.24+8.76)+0.78 =10+0.78 =10.78
84. 933-157-43 =933-(157+43)=933-200=733
85. 4821-998 =4821-1000+2=382
1、1.25×(8+10)
=1.25×8+1.25×10
=10+12.5
=22.5
2、1.24+0.78+8.76
=(1.24+8.76)+0.78
=10+0.78
=10.78
3、1/2-(4/5-1/2)
=1/2+1/2-4/5
=1-4/5
=1/5
4、4800÷25÷4
=4800÷(25x4)
=4800÷100
=4800÷100
=48
5、2/5-(3/8-3/5)
=2/5+3/5-3/8
=1-3/8
=5/8
6、3/4-(3/7-1/4)
=3/4+1/4-3/7
=1-3/7
=4/7
7、3.2x0.125x2.5
=0.125x8x(0.4x2.5)
=1x1
=1
8、0.4×125×25×0.8
=(0.4×25)×(125×0.8)
=10×100
=1000
9、1.25×(8+10)
=1.25×8+1.25×10
=10+12.5
=22.5
10、9123-(123+8.8)
=9123-123-8.8
=9000-8.8
=8991.2
1.6÷ 3/8 – 3/8 ÷6
=1/6x(3/8-3/8)
=1/6x0
=0
2.4/7 × 5/9 + 3/7 × 5/9
=(4/7+3/7)x5/9
=1x5/9
=5/9
3.5/2 -（ 3/2 + 4/5 ）
=5/2-3/2-4/5
=1-4/5
=1/5
4.6 ×（ 1/2 + 2/3 ）
=6x1/2+6x2/3
=3+4
=7
5.8 × 4/5 + 8 × 11/5
=8x(4/5+11/5)
=8x3
=24
6.31 × 5/6 – 5/6
=(31-1)x5/6
=30x5/6
=25
7.4/5 × 25/16 + 2/3 × 3/4
=5/4+1/2
=5/4+2/4
=7/4
8.101 × 1/5 – 1/5 × 21
=(101-21)x1/5
=80x1/5
=16
1. 0.4×125×25×0.8 =（0.4×25）×（125×0.8）=10×100=1000
2. 1.25×（8+10）=1.25×8+1.25×10 =10+12.5=22.5
3.9123-（123+8.8）=9123-123-8.8=9000-8.8=8991.2
4.1.24×8.3+8.3×1.76 =8.3×（1.24+1.76） =8.3×3=24.9
5.9999×1001=9999×（1000+1）=9999×1000+9999×1=10008999
6. 14.8×6.3-6.3×6.5＋8.3×3.7=（14.8-6.5）×6.3＋8.3×3.7=8.3×6.3+8.3×3.7=8.3×（6.3＋3.7）=8.3×10=83
7. 1.24+0.78+8.76=（1.24+8.76）+0.78=10+0.78=10.78
8. 933-157-43 =933-（157+43） =933-200 =733
9. 4821-998=4821-1000+22=3823
10. 32×125×25=4×8×125×25=（4×25）×（8×125）=100×1000=100000 9048÷26=（2600+2600+2600+1248）÷26=2600÷26+2600÷26+2600÷26+1248÷26=100+100+100+48=348
11. 2881÷ 43=（1290+1591）÷ 43=1290÷43+1591÷43=30+37 =67 3.2×42.3×3.75-12.5×0.423×16=3.2×42.3×3.75-1.25×42.3×1.6=42.3×(3.2×3.75-1.25×1.6)=42.3×(4×0.8×3.75-1.25×4×0.4)=42.3×(4×0.4×2×3.75-1.25×4×0.4)=42.3×(4x0.4x7.5-1.25x4x0.4)=42.3×[4×0.4×(7.5-1.25)]=42.3×[4×0.4×6.25]=42.3×(4×2.5) =423
12. 1.8+18÷1.5-0.5×0.3 =1.8+12-0.15=13.8-0.15 =13.65
13. 6.5×8+3.5×8-47 =52+28-47 =80-47 =33 (80-9.8)×5分之2-1.32 =70.2X2/5-1.32=28.08-1.32 =26.76
14. 8×7分之4÷[1÷(3.2-2.95)] =8×4/7÷[1÷0.25]=8×4/7÷4 =8/7
15. 2700×（506－499）÷900 =2700×7÷900 =18900÷900 =21
16. 33.02－（148.4－90.85）÷2.5=33.02－57.55÷2.3=33.02－23.02=10
17. （1÷1－1）÷5.1 =（1－1）÷5.1 =0÷5.1 =0
18. 18.1＋（3－0.299÷0.23）×1=18.1＋1.7×1 =18.1＋1.7 =19.8
19. 9000÷72×(1.25×0.7×8)=9000÷72×7=125×7=875
20. 61-(1.25+2.5×0.7)=61-3=58
21. [(10-0.8)+9.85]-2÷0.125=19.05-2÷0.125=19.05-16=13.05
22. 5.4÷1.8+240×1.5=3+360=363
23. 9000÷72×(1.25×0.7×8）=9000÷72×7=125×7=875
24. 61-(1.25+2.5×0.7)=61-3=58
25. [(10-0.8)+9.85]-2÷0.125=19.05-2÷0.125=19.05-16=3.05
26. 408－12×24= 408 - 288= 120
27. （46＋28）×60= 74 x 60= 4440
28. 42×50－17 = 2100- 17 = 2083
29. 32＋105÷5 = 32 + 21= 53
30. 420×（327－238） = 420 x 89 = 37380
31. (4121+2389)÷7 = 6510 ÷7 = 930
32. 3.416÷（0.016×35） = 3.416 ÷0.56 = 6.1
33. 0.8×[(10－6.76)÷1.2] = 0.8 x(3.24÷1.2) = 0.8 x 2.7 = 2.16
34. 5.67×0.2-0.62 = 1.134-0.62 = 0.514
35.0.4×0.7×0.25 = 0.4 x 0.2 5 x 0.7 = 0.1 x 0.7 = 0.07
36. 0.78+5.436+1 = 6.216 +1 = 7.216
37. 30.8÷[14－(9.85＋1.07)] = 30.8 ÷ (14 - 10.92) = 30.8÷3.08 = 10
38. [60－(9.5＋28.9)]÷0.18 = (60- 38.4)÷0.18 = 21.6 ÷0.18 = 120
39. 2.881÷0.43－0.24×3.5 = 6.7 - 0.24 x3.5 = 6.7 - 0.84 = 5.86
40. 20×[(2.44－1.8)÷0.4＋0.15] = 20x (0.64 ÷0.4 +0.15)= 20x(1.6 +0.15) = 20 x1.75 = 35
41. 28-(3.4+1.25×2.4) = 28 - (3.4 + 3) = 28 - 6.4 = 21.6
42. 2.55×7.1+2.45×7.1 = (2.55 + 2.45) x7.1 = 5 x7.1=35.5
43. 0.8×〔15.5-(3.21+5.79)〕 = 0.8 x (15.5 - 9) = 0.8 x 6.5 = 5.2
44.（31.8+3.2×4）÷5 = (31.8 + 12.8)÷5 = 44.6÷5 = 8.92
45. 31.5×4÷(6+3) = 126 ÷ 9 = 14
46. 2÷2.5+2.5÷2 = 0.8 + 1.25 =2.05
47. 194－64.8÷1.8×0.9 = 194 -36 x0.9 = 194-32.4 = 161.65180－705×6 = 5180 - 4230=950
48. 24÷2.4－2.5×0.8 =10 -2=8
49. 405×(3213-3189) =405x24 = 9720
59. 125×(97-81) =125x16 =2000
60. 6942+480÷3 = 6942 + 160 = 6782
61. 20+80÷4-20 = 20 + 20 -20 = 40 -20 = 20
62. 100÷（32-30）×0 = 100 ÷2 x0= 50 x0 = 0
63. 25×4-12×5 = 100 - 60 = 40
64. 70×〔（42-42）÷18〕=70 x (0÷18) = 70x0 = 0
65. 75×65+75×35 = 75 x (65 +35) = 75x100 = 7500
66. 6-1.6÷4= 6- 0.4 = 5.6
67. 5.38+7.85-5.37= 13.23 - 5.37=7.86
68. 7.2÷0.8-1.2×5=9 - 6 =3
69. 6-1.19×3-0.43= 6-3.57 - 0.43 = 6- (3.57 + 0.43) = 6-4 = 2
70. 6.5×（4.8-1.2×4）= 6.5 x(4.8 - 4.8 )=6.5 x0 = 0
71. 0.68×1.9+0.32×1.9 = (0.68 + 0.32) x1.9 = 1 x 1.9 = 1.9
72. 10.15-10.75×0.4-5.7 = 10.15 - 4.3 - 5.7 = 10.15 -(4.3 + 5.7)=10.15 - 10 =0.15
73. 5.8×（3.87-0.13）+4.2×3.74 = 5.8 x 3.74 +4.2 x 3.74 = (5.8 +4.2)x3.74 = 10 x 3.74 = 37.4
74. 32.52-（6+9.728÷3.2）×2.5 = 32.52 - (6+3.04)x2.5 = 32.52 - 9.02 x 2.5 = 32.52 -22.55 = 9.97
75.（136+64）×（65-345÷23）= 200x(65-15) = 200x 50=10000
76. 0.4×125×25×0.8 =(0.4×25)×(125×0.8)=10×100=1000
77. 1.25×(8+10) =1.25×8+1.25×10=10+12.5=22.5
78. 9123-(123+8.8) =9123-123-8.8=9000-8.8=8991.2
79. 1.24×8.3+8.3×1.76 =8.3×(1.24+1.76)=8.3×3=24.9
80. 9999×1001 =9999×(1000+1)=9999×1000+9999×1 =10008999
81. 14.8×6.3-6.3×6.5+8.3×3.7 =(14.8-6.5)×6.3+8.3×3.7=8.3×6.3+8.3×3.7
82. 8.3×(6.3+3.7) =8.3×10 =83
83. 1.24+0.78+8.76 =(1.24+8.76)+0.78 =10+0.78 =10.78
84. 933-157-43 =933-(157+43)=933-200=733
85. 4821-998 =4821-1000+2=382