| 计算: 3000-36×42÷14 | 4.5×2.4-6÷1.2 | 2![]() |
(2 )÷2![]() | (1.6- )÷(1 ) | [5.4+(4 )×1 ]÷1 . |
=3000-36×(42÷14),
=3000-36×3,
=3000-108,
=2892;
4.5×2.4-6÷1.2
=4.5×2×1.2-5,
=10.8-5,
=5.8;
2

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=[5.4+(4.375-3.25)×1.6]÷1.4,
=[5.4+1.125×1.6]÷1.4,
=[5.4+1.8]÷1.4,
=7.2÷1.4,
=
.分析:算式3000-36×42÷14可根据乘法结合律进行计算;
算式4.5×2.4-6÷1.2可将2.4拆分为2×1.2进行计算;
其余算式根据四则混合运算的运算顺序计算即可:先算乘除,再算加减,有括号要先算括号里面的.
点评:本题中大部分题目不能简算,因此计算时要细心,注意通分约分及小数与分数的互化.