题目内容
用你喜欢的方法计算. 0.6+0.94-0.208 | 4.85×1.25×8 | (64-22.4÷1.4)×1.2 |
18.3-6.25-3.75 | 2.8×3.6+1.4×2.8 | 6.6÷〔14.5-(1.7+1.8)〕 |
解:
(1)0.6+0.94-0.208,
=1.54-0.208,
=1.332;
(2)4.85×1.25×8,
=4.85×(1.25×8),
=4.85×10,
=48.5;
(3)(64-22.4÷1.4)×1.2,
=(64-16)×1.2,
=48×1.2,
=57.6;
(4)18.3-6.25-3.75,
=18.3-(6.25+3.75),
=18.3-10,
=8.3;
(5)2.8×3.6+1.4×2.8,
=2.8×(3.6+1.4),
=2.8×5,
=14;
(6)6.6÷[14.5-(1.7+1.8)],
=6.6÷[14.5-3.5],
=6.6÷11,
=0.6.
分析:(1)先计算加法,再计算减法;
(2)根据乘法结合律进行简算;
(3)先计算小括号里面的除法,再计算小括号里面的减法,最后计算小括号外面的乘法;
(4)18.3连续减去6.25与3.75,等于减去6.25与3.75的和;
(5)根据乘法分配律进行简算;
(6)先计算小括号里面的加法,再计算中括号里面的减法,最后计算除法.
点评:根据小数四混合运算的运算顺序进行计算即可,能简算要简算.
(1)0.6+0.94-0.208,
=1.54-0.208,
=1.332;
(2)4.85×1.25×8,
=4.85×(1.25×8),
=4.85×10,
=48.5;
(3)(64-22.4÷1.4)×1.2,
=(64-16)×1.2,
=48×1.2,
=57.6;
(4)18.3-6.25-3.75,
=18.3-(6.25+3.75),
=18.3-10,
=8.3;
(5)2.8×3.6+1.4×2.8,
=2.8×(3.6+1.4),
=2.8×5,
=14;
(6)6.6÷[14.5-(1.7+1.8)],
=6.6÷[14.5-3.5],
=6.6÷11,
=0.6.
分析:(1)先计算加法,再计算减法;
(2)根据乘法结合律进行简算;
(3)先计算小括号里面的除法,再计算小括号里面的减法,最后计算小括号外面的乘法;
(4)18.3连续减去6.25与3.75,等于减去6.25与3.75的和;
(5)根据乘法分配律进行简算;
(6)先计算小括号里面的加法,再计算中括号里面的减法,最后计算除法.
点评:根据小数四混合运算的运算顺序进行计算即可,能简算要简算.
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