《2025年快乐口算五年级数学上册人教版》

1 算一算。
15×0.3= 3+0.3×0.5=
0.4×2.5= 5×0.4-1=
0.8×12.5= 1.25×2×0.4=
20×0.02= 3×0.2×0.5=
0.32×0.3= 4×3.7×0.25=
0.2×0.5= 5+0.17×0.1=
7×0.02= 0.4×1.5×10=
0.4×0.25= 8×1.25×4=
0.5×0.8= 0.7×6+6×0.3=
2.19×20= 1.7×25×4=
0.58×0.5= 1.8×6-1.8=
0.16×6= 10-0.8×10=
0.6×0.5= 1.12×100-90=
0.4×8= 0.7×(0.52+0.48)=
3.5×0.6= 8-1×0.2=
3.2×1= 4.4×4+5.6×4=
0.9×100= 0.05×0.8+2=

答案： 15×0.3=4.5
3+0.3×0.5=3+0.15=3.15
0.4×2.5=1
5×0.4-1=2-1=1
0.8×12.5=10
1.25×2×0.4=1.25×0.8=1
20×0.02=0.4
3×0.2×0.5=3×0.1=0.3
0.32×0.3=0.096
4×3.7×0.25=4×0.25×3.7=1×3.7=3.7
0.2×0.5=0.1
5+0.17×0.1=5+0.017=5.017
7×0.02=0.14
0.4×1.5×10=0.6×10=6
0.4×0.25=0.1
8×1.25×4=10×4=40
0.5×0.8=0.4
0.7×6+6×0.3=6×(0.7+0.3)=6×1=6
2.19×20=43.8
1.7×25×4=1.7×100=170
0.58×0.5=0.29
1.8×6-1.8=1.8×(6-1)=1.8×5=9
0.16×6=0.96
10-0.8×10=10-8=2
0.6×0.5=0.3
1.12×100-90=112-90=22
0.4×8=3.2
0.7×(0.52+0.48)=0.7×1=0.7
3.5×0.6=2.1
8-1×0.2=8-0.2=7.8
3.2×1=3.2
4.4×4+5.6×4=4×(4.4+5.6)=4×10=40
0.9×100=90
0.05×0.8+2=0.04+2=2.04

2 比一比。
6.5×0.98$◯$6.5
5.09×1.2$◯$5.09
8.25×1.01$◯$8.25
3.8×6.5$◯$6.5×3.8
18×0.35$◯$0.35
6.3×2.04$◯$2.04
24.2×0.7$◯$24.2
25.6×1.1$◯$25.6
4.25×1.1$◯$4.25×0.9
2.3×0.6$◯$0.6
3.6×0.3$◯$0.3
37×0.54$◯$3.7×0.54
6.5×1$◯$6.5-1
25×0.2$◯$25×0.02
1×0.99$◯$1
8.23×0$◯$8.23×1
0.006×78$◯$7.8×0.6

答案： 1. $6.5×0.98 \lt 6.5$
2. $5.09×1.2 \gt 5.09$
3. $8.25×1.01 \gt 8.25$
4. $3.8×6.5 = 6.5×3.8$
5. $18×0.35 \gt 0.35$
6. $6.3×2.04 \gt 2.04$
7. $24.2×0.7 \lt 24.2$
8. $25.6×1.1 \gt 25.6$
9. $4.25×1.1 \gt 4.25×0.9$
10. $2.3×0.6 \gt 0.6$
11. $3.6×0.3 \gt 0.3$
12. $37×0.54 \gt 3.7×0.54$
13. $6.5×1 \gt 6.5 - 1$
14. $25×0.2 \gt 25×0.02$
15. $1×0.99 \lt 1$
16. $8.23×0 \lt 8.23×1$
17. $0.006×78 \lt 7.8×0.6$