2025年同步练习册山东五年级数学上册青岛版第134页答案
(2)用竖式计算。(带“※”的要验算。)
2.04×43=
※5.76÷1.2=
3.1÷0.13≈(得数保留两位小数。)

答案


87.72,4.8,23.85
(3)脱式计算。(能简算的要简算。)
1.25×27×0.8
=1.25×0.8×27
=1×27
=27
301×6.5-6.5
=(301-1)×6.5
=300×6.5
=1950
3.75÷0.25÷0.4
=3.75÷(0.25×0.4)
=3.75÷0.1
=37.5
2.4×99
=2.4×(100-1)
=2.4×100-2.4×1
=240-2.4
=237.6

答案

1.25×27×0.8
=1.25×0.8×27
=1×27
=27
301×6.5-6.5
=(301-1)×6.5
=300×6.5
=1950
3.75÷0.25÷0.4
=3.75÷(0.25×0.4)
=3.75÷0.1
=37.5
2.4×99
=2.4×(100-1)
=2.4×100-2.4×1
=240-2.4
=237.6
(4)解方程。
2x-1.35x= 65
0.65x=65，x=65÷0.65，x=100

7x+2.4×3= 17.7
7x+7.2=17.7，7x=17.7-7.2，7x=10.5，x=10.5÷7，x=1.5

2x-0.9= 5.1
2x=5.1+0.9，2x=6，x=6÷2，x=3

5x+4= 4.2
5x=4.2-4，5x=0.2，x=0.2÷5，x=0.04

答案

2x-1.35x=65
0.65x=65
x=65÷0.65
x=100
7x+2.4×3=17.7
7x+7.2=17.7
7x=17.7-7.2
7x=10.5
x=10.5÷7
x=1.5
2x-0.9=5.1
2x=5.1+0.9
2x=6
x=6÷2
x=3
5x+4=4.2
5x=4.2-4
5x=0.2
x=0.2÷5
x=0.04