题目内容
用你喜欢的方法计算.
|
|
| ||||||||||||||||
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| 20×(1+
|
考点:分数的简便计算
专题:运算定律及简算
分析:(1)直接约分计算即可;
(2)直接约分计算即可;
(3)先去括号,再约分计算即可;
(4)直接约分计算即可;
(5)运用乘法的分配律进行简算;
(6)运用乘法的分配律进行简算.
(2)直接约分计算即可;
(3)先去括号,再约分计算即可;
(4)直接约分计算即可;
(5)运用乘法的分配律进行简算;
(6)运用乘法的分配律进行简算.
解答:
解:(1)
×
×
=
=
;
(2)
×15×
=
=
;
(3)
×(
×
)
=
×
×
=
=
;
(4)
×42×
=
=21;
(5)
×98+
×2
=
×(98+2)
=
×100
=80;
(6)20×(1+
)
=20×1+20×
=20+5
=25.
| 6 |
| 11 |
| 3 |
| 6 |
| 12 |
| 11 |
=
| 6×3×12 |
| 11×6×11 |
=
| 36 |
| 121 |
(2)
| 2 |
| 5 |
| 6 |
| 7 |
=
| 2×15×6 |
| 5×7 |
=
| 36 |
| 7 |
(3)
| 2 |
| 3 |
| 9 |
| 10 |
| 6 |
| 5 |
=
| 2 |
| 3 |
| 9 |
| 10 |
| 6 |
| 5 |
=
| 2×9×6 |
| 3×10×5 |
=
| 18 |
| 25 |
(4)
| 6 |
| 7 |
| 7 |
| 12 |
=
| 6×42×7 |
| 7×12 |
=21;
(5)
| 4 |
| 5 |
| 4 |
| 5 |
=
| 4 |
| 5 |
=
| 4 |
| 5 |
=80;
(6)20×(1+
| 1 |
| 4 |
=20×1+20×
| 1 |
| 4 |
=20+5
=25.
点评:此题考查了运算定律与简便运算,四则混合运算,注意运算顺序和运算法则,灵活运用所学的运算律简便计算.
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