四年级小数简便运算及答案

=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
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
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
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
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
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
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
=6.3
=26
=4.182
=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
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
=2.5×12.5×(8×4） =42×67+42×33
=(2.5×4)×(12.5×8) =42×(67+33）
=10×100
=42×100
来自百度文库
=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）
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
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
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
=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)
=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
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