苏教版数学五年级上册--小数四则混合运算及其巧算(含答案)
小学数学五年级上册苏教版--小数四则混合运算及其巧算
1.计算下面各题,能简便的要用简便方法算。
(1)3.6+3.15÷(31-29.5)
(2)101×7.5-7.5
(3)5.45×1.9+8.1×5.45
(4)42.6÷1.25÷0.8
2.计算下面各题.
(1)6.8÷0.05×0.5
(2)5.12﹣(3.2+0.56)÷0.8
(3)2.02×135
(4)3.72÷2.5÷0.4
3.用简算方法计算下列各题。
(1)25×0.32×1.25
(2)6.85-2.13-1.87
(3)28.6×10.1-2.86
4.计算下面各题,能简便的要用简便方法计算。
(1)0.36+9.6÷3.2
(2)1.25×6.8×8
(3)0.57×99+0.57
5.计算下面各题,能简算的要简算
(1)9.07﹣22.78÷3.4
(2)2.5×3.2×1.25
(3)25.7×10.1
(4)6.1×3.6+3.6×3.9
6.脱式计算,能简算的要简算。
(1)17.8×8.4+17.8×1.6
(2)0.25×3.2×0.125
(3)64.2×5.1-6.42
(4)13.5÷27÷(2-1.98)
7.用自己喜欢的方法计算。
(1)5.4÷(3.6-0.9)
(2)6.8×99+6.8
(3)1.75÷2.5÷0.4
8.计算下面各题(能简算的要简算)。
(1)0.18×101
(2)17.6-7.6×1.4-5.36
(3)21.6÷0.8-5.2×2.5
(4)4.18×1.5÷4.18×1.5
9.脱式计算(能简算的要简算)。
(1)0.75×4×0.25×4
(2)6.3×10.1
(3)4.536÷0.8÷14
(4)2.8×3.6+1.4×2.8
10.计算题:
(1)7.44÷[(54.7-17.5)×0.5]
(2)8.1×1.3+8÷1.3+1.9×1.3-11.9÷1.3
11.计算下面各题,能简算的要简算。
(1)80-(8.8+2.2)×1.4
(2)86.4÷0.24×0.25
(3)4×0.8×12.5×2.5
(4)(455-12.5×4)÷0.81
(5)1.08÷[(0.4+0.5)×0.6]
(6)18.74×0.18+1.26×0.18
12.简便计算。
(1)5.67×99+5.67
(2)6.9×11.3+11.3×3.1
13.用你喜欢的方法计算。
(1)80.8×101-80.8
(2)10.7×[0.6÷(1-0.98)]
(3)4.2×0.34-1.6÷40
(4)78÷0.25÷0.4
14.脱式计算,能简算的要简算。
(1)16.4÷25÷4
(2)6.9×3.6+3.6×3.1
(3)14.4+1.25÷0.5
(4)(16.8+4.9)÷0.7
15.计算下面各题,能简算的要简算。
(1)0.9+9.6÷0.32
(2)0.11×1.8+8.2×0.11
(3)5×1.77×0.2
(4)(7.5-2.3×0.4)÷0.2
16.能用简便方法计算的用简便方法计算。
①4.8×18.4+4.8×1.6
②1.72+0.28×1.2
③8.5×101-8.5
④0.25×1.25×3.2
⑤135÷[(3.45-1.65)×2.5]
⑥3.7÷2.5÷0.4
答案解析部分
1.【答案】(1)3.6+3.15÷(31-29.5)
=3.6+3.15÷1.5
=3.6+2.1
=5.7
(2)101×7.5-7.5
=(101-1)×7.5
=100×7.5
=750
(3)5.45×1.9+8.1×5.45
=5.45×(1.9+8.1)
=5.45×10
=54.5
(4)42.6÷1.25÷0.8
=42.6÷(1.25×0.8)
=42.6÷1
=42.6
2.【答案】(1)解:6.8÷0.05×0.5
=136×0.5
=68
(2)解:5.12﹣(3.2+0.56)÷0.8
=5.12﹣3.76÷0.8
=5.12﹣4.7
=0.42
(3)解:2.02×135
=(2+0.02)×135
=2×135+0.02×135
=270+2.7
=272.7
(4)解:3.72÷2.5÷0.4
=3.72÷(2.5×0.4)
=3.72÷1
=3.72
3.【答案】(1)25×0.32×1.25
=25×0.4×0.8×1.25
=(25×0.4)×(0.8×1.25)
=10×1
=10
(2)6.85-2.13-1.87
=6.85-(2.13+1.87)
=6.85-4
=2.85
(3)28.6×10.1-2.86
=2.86×101-2.86
=2.86×(101-1)
=2.86×100
=286
4.【答案】(1)0.36+9.6÷3.2
= 0.36+3
=3.36
(2)1.25×6.8×8
= 1.25×8×6.8
=10×6.8
=68
(3)0.57×99+0.57
=0.57×(99+1)
=0.57×100
=57
5.【答案】(1)9.07﹣22.78÷3.4
=9.07﹣6.7
=2.37
(2)2.5×3.2×1.25
=2.5×(4×0.8)×1.25
=(2.5×4)×(0.8×1.25)
=10×1
=10
(3)25.7×10.1
=25.7×(10+0.1)
=25.7×10+25.7×0.1
=257+2.57
=259.57
(4)6.1×3.6+3.6×3.9
=(6.1+3.9)×3.6
=10×3.6
=36
6.【答案】(1)17.8×8.4+17.8×1.6
=17.8×(8.4+1.6)
=17.8×10
=178
(2)0.25×3.2×0.125
=(0.25×4)×(0.125×0.8)
=1×0.1
=0.1
(3)64.2×5.1-6.42
=6.42×51-6.42
=6.42×(51-1)
=6.42×50
=321
(4)13.5÷27÷(2-1.98)
=13.5÷27÷0.02
=0.5÷0.02
=25
7.【答案】(1)5.4÷(3.6-0.9)
=5.4÷2.7
=2
(2)6.8×99+6.8
=6.8×(99+1)
=6.8×100
=680
(3)1.75÷2.5÷0.4
=1.75÷(2.5×0.4)
=1.75÷1
=1.75
8.【答案】(1)0.18×101
=0.18×(100+1)
=0.18×100+0.18×1
=18+0.18
=18.18
(2)17.6-7.6×1.4-5.36
=17.6-10.64-5.36
=17.6-(10.64+5.36)
=17.6-16
=1.6
(3)21.6÷0.8-5.2×2.5
=27-13
=14
(4)4.18×1.5÷4.18×1.5
=4.18÷4.18×1.5×1.5
=1×1.5×1.5
=2.25
9.【答案】(1)0.75×4×0.25×4
=(0.75×4)×(0.25×4)
=3×1
=3
(2)6.3×10.1
=6.3×(10+0.1)
=6.3×10+6.3×0.1
=63+0.63
=63.63
(3)4.536÷0.8÷14
=4.536÷(0.8×14)
=4.536÷11.2
=0.405
(4)2.8×3.6+1.4×2.8
=2.8×(3.6+1.4)
=2.8×5
=14
10.【答案】(1)7.44÷[(54.7-17.5)×0.5]
=7.44÷[37.2×0.5]
=7.44÷18.6
=0.4
(2)8.1×1.3+8÷1.3+1.9×1.3-11.9÷1.3
=(8.1+1.9)×1.3-(11.9-8)÷1.3
=10×1.3-3.9÷1.3
=13-3
=10
11.【答案】(1)80-(8.8+2.2)×1.4
=80-11×1.4
=80-15.4
=64.6
(2)86.4÷0.24×0.25
=360×0.25
=90
(3)4×0.8×12.5×2.5
=(4×2.5)×(0.8×12.5)
=10×10
=100
(4)(455-12.5×4)÷0.81
=(455-50)÷0.81
=405÷0.81
=500
(5)1.08÷[(0.4+0.5)×0.6]
=1.08÷0.9×0.6
=1.08÷0.54
=2
(6)18.74×0.18+1.26×0.18
=0.18×(18.74+1.26)
=0.18×20
=3.6
12.【答案】(1)5.67×99+5.67
=5.67×99+5.67×1
=5.67×(99+1)
=5.67×100
=567
(2)6.9×11.3+11.3×3.1
=11.3×(6.9+3.1)
=11.3×10
=113
13.【答案】(1)80.8×101-80.8
=80.8×101-80.8×1
=80.8×(101-1)
=80.8×100
=8080
(2)10.7×[0.6÷(1-0.98)]
=10.7×(0.6÷0.02)
=10.7×30
=321
(3)4.2×0.34-1.6÷40
=1.428-0.04
=1.388
(4)78÷0.25÷0.4
=78÷(0.25×0.4)
=78÷0.1
=780
14.【答案】(1)16.4÷25÷4
=16.4÷(25×4)
=16.4÷100
=0.164
(2)6.9×3.6+3.6×3.1
=3.6×(6.9+3.1)
=3.6×10
=36
(3)14.4+1.25÷0.5
=14.4+2.5
=16.9
(4)(16.8+4.9)÷0.7
=21.7÷0.7
=31
15.【答案】(1)0.9+9.6÷0.32
=0.9+30
=30.9
(2)0.11×1.8+8.2×0.11
=0.11×(1.8+8.2)
=0.11×10
=1.1
(3)5×1.77×0.2
=5×0.2×1.77
=1×1.77
=1.77
(4)(7.5-2.3×0.4)÷0.2
=(7.5-0.92)÷0.2
=6.58÷0.2
=32.9
16.【答案】①4.8×18.4+4.8×1.6=4.8×(18.4+1.6)=4.8×20=96②1.72+0.28×1.2=1.72+0.336=2.056③8.5×101-8.5=8.5×(101-1)=8.5×100=850④0.25×1.25×3.2=0.25×1.25×(4×0.8)=(0.25×4)×(1.25×0.8)=1×1=1⑤135÷[(3.45-1.65)×2.5]=135÷[1.8×2.5]=135÷4.5=30⑥3.7÷2.5÷0.4=3.7÷(2.5×0.4)=3.7÷1=3.7