2026年小学必刷题六年级数学上册苏教版第14页答案
1.简便计算:0.279×343+0.657×279。

答案

原式=0.279×343+657×0.279
=0.279×(343+657)
=0.279×1000
=279
2. 简便计算。
(1)$7.6×84+76×1.6$
(2)$12.5×0.54+0.067×125-1.25×4.1$

答案

(1)原式=7.6×84+7.6×16
=7.6×(84+16)
=7.6×100
=760
(2)原式=12.5×0.54+0.67×12.5-12.5×0.41
=12.5×(0.54+0.67-0.41)
=12.5×0.8
=10
3.简便计算:0.999×1.3－0.111×2.7

答案

原式=(0.111×9)×1.3-0.111×2.7
=0.111×(9×1.3)-0.111×2.7
=0.111×11.7-0.111×2.7
=0.111×(11.7-2.7)
=0.111×9
=0.999
【解析】此题还可以让0.999不变,将2.7变为(9×0.3),再将0.111×2.7变为0.999×0.3,然后运用乘法分配律进行计算。
4.简便计算:0.88×2.1+0.44×2.6-0.22×3.6

答案

原式=0.22×4×2.1+0.22×2×2.6-0.22×3.6
=0.22×(4×2.1)+0.22×(2×2.6)-0.22×3.6
=0.22×8.4+0.22×5.2-0.22×3.6
=0.22×(8.4+5.2-3.6)
=0.22×10
=2.2
5. 简便计算。
$3.79× 0.38+1.59× 6.21+3.79× 1.21$

答案

原式=3.79×(0.38+1.21)+1.59×6.21
=3.79×1.59+1.59×6.21
=1.59×(3.79+6.21)
=1.59×10
=15.9
6.简便计算。
$5.78×8.8+6.15×4.22-57.8×0.265$

答案

原式=5.78×8.8+6.15×4.22-5.78×2.65
=5.78×(8.8-2.65)+6.15×4.22
=5.78×6.15+6.15×4.22
=6.15×(5.78+4.22)
=6.15×10
=61.5
7. 简便计算。
$(1+0.53+0.39)×(0.53+0.39+0.77)-(1+0.53+0.39+0.77)×(0.53+0.39)$

答案

设A=1+0.53+0.39,B=0.53+0.39。
原式=A×(B+0.77)-(A+0.77)×B
=A×B+0.77×A-A×B-0.77×B
=0.77×(A-B)
=0.77×(1+0.53+0.39-0.53-0.39)
=0.77×1
=0.77
8. 简便计算。
$(1+0.12+0.23)×(0.12+0.23+0.34)-(1+0.12+0.23+0.34)×(0.12+0.23)$

答案

设A=1+0.12+0.23,B=0.12+0.23。
原式=A×(B+0.34)-(A+0.34)×B
=A×B+0.34×A-A×B-0.34×B
=0.34×(A-B)
=0.34×(1+0.12+0.23-0.12-0.23)
=0.34×1
=0.34