四年级小数简便运算及答案精编版

2.38×4.1+5.8×2.38+0.238 =2.38×4.1+5.8×2.38+2.38×0.1 =2.38 ×(4.1+5.8+0.1） =2.38×10 =23.8
28.7×1.6÷28.7
= 28.7÷28.7×1.6 =1×1.6 =1.6
11÷0.25－10÷0.25 =(11 －10)÷0.25 =1÷0.25 =4
一、用简便方法计算下面各题：
48.7+5.6+11.3 43.21+98.76+56.79+1.24
5.48+3.99
=48.7+11.3+5.6 =(43.21+56.79)+(98.76+1.24)=5.48+(4－0.01)
=60+5.6
=100+100
=5.48+4－0.01
=65.6
=200
14×72+42×76
=14×3×(72÷3)+42×76 =42×24+42×76 =42×(24+76) =4200
50×96+57×4+7×66
399.6×9－1998×0.8
= 399.6×9－1998×2×0.4 = 399.6×9－399.6×4 = 399.6×5 =1998
654321×123456－654322×123455
23.12－(10.12－3.67) =23.12－10.12+3.67 =13+3.67 =16.67
20.65－(17.1－1.35)
=20.65+1.35－17.1 =22－17.1 =4.9
32.75+(15.25－10.68) =32.75+15.25－10.68 =48－10.68 =37.32
1.25×13×1.6
10.2×0.41
=0.25×7×(4×0.9） =1.25×13×(8×0.2）= (10+0.2）×0.41
=0.25×4×7×0.9 =1.25×8×13×0.2 =10×0.41+0.2×0.41
=1×7×0.9
=10×13×0.2
=4.1+0.082
Βιβλιοθήκη Baidu=6.3
=26
=4.182
88×0.125 =(80+8)×0.125 =80×0.125+8×0.125 =10+1 =11
1234×9876－1233×9877
=1233×9876+1×9876－(1233×9876+1233×1)
=9876－1233 =8643
(8.4+8.4+8.4+8.4)×2.5 =8.4×4×2.5 =8.4×(4×2.5)
=2.5×12.5×(8×4） =42×67+42×33
=(2.5×4)×(12.5×8) =42×(67+33）
=10×100
=42×100
=1000
=4200
8.37×16÷8
=8.37×(16÷8） =8.37×2 =16.74
28.7÷0.35
310÷2.5÷4
=28.7÷(0.7×0.5）=310÷(2.5×4）
=999000－999+1999
=49.5×13+50.5×13
=1000000
=(49.5+50.5)×13 =1300
111×36+888×8 =111×36+111×8×8 =111×(36+64)
=11100
98×98+97×97－98×97－97×96 =98×98－98×97+97×97－97×96 =98×(98－97)+97×(97－96) =98×1+97×1 =197
1999×19981998－1998×19991999
=1999×1998×10001－1998×1999×10001
=0
999×999+1999
= 999×(1000－1)+1999
49.5×13.5－0.5×49.5+50.5×13 = 999×1000－1×999+1999
=49.5×(13.5－0.5)+50.5×13
=9.47
6.3+15.4+0.09+3.7+14.6 56.8+22.8 34.65－0.99－0.97
=(6.3+3.7)+(14.6+15.4)+0.09 =56.8+23－0.2 =34.65－1－1+(0.01+
=40+0.09
=79.8－0.2 =32.65+0.04
=40.09
=79.6
=84
98+97－96－95+94+93－92－91+……+6+5－4－3+2+1
= (98+97－96－95)+(94+93－92－91)+……+(6+5－4－3)+2+1 =4×〔(98－2)÷4〕+2+1 =4×24+2+1 =99
0.9+0.99+0.999+0.9999
12.9÷0.72+43.5÷3.6
30.16－23.28+15.28 0.25×4.78×4
=30. 16－(23.28－15.28) =0.25×4×4.78
=30.16－8
=1×4.78
=22.16
=4.78
0.98×2.5 = (1－0.02) ×2.5
=1×2.5－0.02×2.5
=2.5－0.05
=2.45
0.25×7×3.6
0.7+2×1.4+2.1+2×0.7 =0.7×1+(2×2)×0.7+0.7×3+2×0. 7
=0.7×(1+4+3+2)
=0.7×10
=7
(0.375×101－37.5)÷37.5 =0.375×(101－1)÷37.5 =0.375×100÷37.5 =37.5÷37.5 =1
1.1×1.1×11－1.1×1.1－1.1 =1.1×1.1×(11－1)－1.1 =1.1×11－1.1 =1.1×(11－1) =11
7.6×18+2.3×2.4
1.62÷8÷(3.62－2.37) =1.62÷8÷1.25
=1.62÷(8×1.25）
=1.62÷10
=0.162
0.38×7.6+0.38÷2.5+0.38×2 36×2.54+1.8×49.2
=0.38×7.6+0.38×0.4+0.38×2 =1.8×20×2.54+1.8×49.2
7.8×(1.001÷0.26)×0.26 =7.8×1.001×(0.26÷0.26) =7.8×1.001 =7.8078
100×9.5×0.98+9.5×2 =100×0.98×9.5+9.5× 2 =9.5×(98+2） =9.5×100 =950
(80+5.6)÷8 =80÷8+5.6÷8 =10+0.7 =10.7
3.5+17.8×99+14.3 =(3.5+14.3)+17.8×99 =17.8×(1+99） =17.8×100 =1780
28×11.11+99.99×8 =28×11.11+11.11×9×8 =28×11.11+11.11×(9×8) =11.11×(28+72） =11.11×100 =1111
23.97+0.9+6.8 23.9+6.78－3.9
=23.97+1+ 7－0.3 =23.9－3.9+6.78
=31.97－0.3
=20+6.78
=31.67
=26.78
31.61－21.27－1.61 =31.61－1.61 －21.27 =30－21.27 =8.73
27.64－(5.79+1.64) =27.64－1.64 －5.79 =26－5.79 =20.21
2003×200220002－2002×20032003
=28.7÷0.7÷0.5 =310÷10
=41÷0.5
=31
=82
560÷(140÷8)
=560÷140×8 =4×8 =32
5.6×7÷4 =5.6÷4×7 =1.4×7 =9.8
11.2÷ 9.6×2.4 =11.2÷(9.6÷2.4） =11.2÷4 =2.8
91÷0.125 =(91×8)÷(0.125×8） =728÷1 =728
===(431－.+8018.+81191+111)－(0.1+0.01+0.001===+(6(0146.2.40.5.09÷50×+134).536).+÷54)(3÷0..537÷.26×3.56)+43.5÷3.6
=30
0.268×8.88÷2.68÷4.44
1.1+1.3+1.5+……+9.7+9.9
=0.38×(7.6+0.4+2)
=1.8×(20×2.54)+1.8×49.2
=0.38×10
=1.8×(50.8+49.2)
=3.8
=1.8×100
1994+199.4+19.94+1.994
=180
=2000+200+20+2－6－0.6－0.06－0.006
=2222－6.666 =2215.334
4.52×0.45+5.48×0.45 =(4.52+5.48）×0.45 =10×0.45 =4.5
42×3.9 = 42×(4－0.1） =42×4－42×0.1 =168－4.2 =163.8
1.4×99+1.4 =1.4×(99+1） =1.4×100 =140
2.5×12.5×32
42×67+4.2×330
3.65－1.28－0.37－1.77
=3.65－(1.28+0.37) －1.77 =3.65－1.65 －1.77 =0.23
19.826－1.173－5.248－3.405
=19.826－(1.173+5.248+3.405 ) =19.826－9.826 =10
130.8－35.9+5.9
=130. 8－(35.9－5.9) =130.8－30 =100.8
1992×27.5+1982×72.5 =(1982+10)×27.5+1982×72.5 =1982×(27.5+72.5)+10×27.5 =198200+275 =198475
96÷3.2÷25
=96÷(0.8×4×25) =96÷80 =1.2
1.6×16+0.4×36
=0.4×4×16+0.4×36 =0.4×(4×16)+0.4×36 =0.4×(64+36) =40
=(0.268÷2.68)×(8.88÷4.44) =(1.1+9.9)÷2×45
=0.1×2
=5.5×45
=0.2
=247.5
117.8÷2.3－4.88÷0.23
=117.8÷2.3－48.8÷2.3 =(117.8－48.8)÷2.3 =69÷2.3 =30
33333×33333
0.225×0.335+0.335×0.775+0.775×0.225
=32.69
34.5－2.98 =34.5－3+0.02 =31.5+0.02 =31.52
45.7－10.4 =45.7－10－0.4 =35.7－0.4 =35.3
57.3－27.8
=57.3－28+0.2 =29.3+0.2 =29.5
67.68－7.3－2.7
=67.68－(7.3+2.7) =67.68－10 =57.68