题目内容
怎样简便怎样算 210-97+83 | 19.8-0.6×7 | + | [7.6-(3.85+2.6)]×0.4 |
(+)×8+ | (++)×24 | 2-2÷3+. |
解:(1)210-97+83,
=210-100+3+83,
=110+3+83,
=196;
(2)19.8-0.6×7,
=19.8-4.2,
=15.6;
(3)+,
=,
=1;
(4)[7.6-(3.85+2.6)]×0.4,
=[7.6-2.6-3.85]×0.4,
=[5-3.85]×0.4,
=1.15×0.4,
=0.46;
(5)(+)×8+,
=×8+×8,
=5+(),
=5+1,
=6;
(6)(++)×24,
=24+24+24,
=12+8+6,
=26;
(7)2-2÷3+,
=1,
=1.
分析:(1)(4)运用减法性质解答,
(2)(3)(7)依据四则运算计算方法,先算第二级运算,再算第一级运算,如果只含有同一级运算,按照从左到右顺序计算,有括号先算括号里面的解答,
(5)先运用乘法分配律再运用加法结合律解答,
(6)运用乘法分配律解答.
点评:本题主要考查学生运用四则运算计算方法,以及正确运用简便算法的能力.
=210-100+3+83,
=110+3+83,
=196;
(2)19.8-0.6×7,
=19.8-4.2,
=15.6;
(3)+,
=,
=1;
(4)[7.6-(3.85+2.6)]×0.4,
=[7.6-2.6-3.85]×0.4,
=[5-3.85]×0.4,
=1.15×0.4,
=0.46;
(5)(+)×8+,
=×8+×8,
=5+(),
=5+1,
=6;
(6)(++)×24,
=24+24+24,
=12+8+6,
=26;
(7)2-2÷3+,
=1,
=1.
分析:(1)(4)运用减法性质解答,
(2)(3)(7)依据四则运算计算方法,先算第二级运算,再算第一级运算,如果只含有同一级运算,按照从左到右顺序计算,有括号先算括号里面的解答,
(5)先运用乘法分配律再运用加法结合律解答,
(6)运用乘法分配律解答.
点评:本题主要考查学生运用四则运算计算方法,以及正确运用简便算法的能力.
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