出10道易错题 六年级下册的 要快.......是数学哦。。。 六年级下册数学难题及答案
\u516d\u5e74\u7ea7\u6570\u5b66\uff0c10\u9053\u7b80\u4fbf\u8ba1\u7b97\u9898\u5e26\u7b54\u6848\u8c22\u8c22\u54e6\u2229_\u2229\uff081\uff092.64\u00d71.7-2.64\u00d70.7
=2.64\u00d7\uff081.7-0.7\uff09
=2.64\u00d71
=2.64
\uff082\uff0931.5\u00d71.07-3.15\u00d70.7
=3.15\u00d710.7-3.15\u00d70.7
=3.15\u00d7\uff0810.7-0.7\uff09
=3.15\u00d710
=31.5
\uff083\uff092.7\u00d75.7-2.7+5.3\u00d72.7
=2.7\u00d7(5.7-1+5.3\uff09
=2.7\u00d710
=27
\uff084\uff090.625\u00f70.125\u00d70.8
=\uff080.625\u00d70.8\uff09\u00d78\u00f7\uff080.128\u00d78\uff09
=0.5\u00d78\u00f71
=4
\uff085\uff0918.6\u00d76.1+3.9\u00d718.6
=18.6\u00d7\uff086.1+3.9\uff09
=18.6\u00d710
=186
\uff086\uff091.3579+3.5791+5.7913+7.9135+9.1357
=\uff081+3+5+7+9\uff09\u00d71.1111
=25\u00d71.1111
=27.7775
\uff087\uff0952.5x2.9+5.45
=5.25x29+5.25+0.2
=5.25\u00d7\uff0829+1\uff09+0.2
=5.25\u00d730+0.2
=157.5+0.3
=157.7
\uff088\uff090.92x15+0.08x15
=\uff080.92+0.08\uff09\u00d715
=1\u00d715
=15
\uff089\uff090.72\u00d71.25\u00d72.5
=0.9\u00d7\uff080.8\u00d71.25\uff09\u00d72.5
=0.9\u00d71\u00d72.5
=2.25
\uff0810\uff09400.6x7-2003x0.4
=200.3x14-200.3x4
=200.3\u00d7\uff0814-4\uff09
=200.3\u00d710
=2003
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2\uff0e\u4fee\u4e00\u6761\u6c34\u6e20\uff0c\u5355\u72ec\u4fee\uff0c\u7532\u961f\u9700\u898120\u5929\u5b8c\u6210\uff0c\u4e59\u961f\u9700\u898130\u5929\u5b8c\u6210\u3002\u5982\u679c\u4e24\u961f\u5408\u4f5c\uff0c\u7531\u4e8e\u5f7c\u6b64\u65bd\u5de5\u6709\u5f71\u54cd\uff0c\u4ed6\u4eec\u7684\u5de5\u4f5c\u6548\u7387\u5c31\u8981\u964d\u4f4e\uff0c\u7532\u961f\u7684\u5de5\u4f5c\u6548\u7387\u662f\u539f\u6765\u7684\u4e94\u5206\u4e4b\u56db\uff0c\u4e59\u961f\u5de5\u4f5c\u6548\u7387\u53ea\u6709\u539f\u6765\u7684\u5341\u5206\u4e4b\u4e5d\u3002\u73b0\u5728\u8ba1\u521216\u5929\u4fee\u5b8c\u8fd9\u6761\u6c34\u6e20\uff0c\u4e14\u8981\u6c42\u4e24\u961f\u5408\u4f5c\u7684\u5929\u6570\u5c3d\u53ef\u80fd\u5c11\uff0c\u90a3\u4e48\u4e24\u961f\u8981\u5408\u4f5c\u51e0\u5929\uff1f
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16\u5929\u5185\u5b9e\u5728\u6765\u4e0d\u53ca\u7684\u624d\u5e94\u8be5\u8ba9\u7532\u4e59\u5408\u4f5c\u5b8c\u6210\u3002\u53ea\u6709\u8fd9\u6837\u624d\u80fd\u201c\u4e24\u961f\u5408\u4f5c\u7684\u5929\u6570\u5c3d\u53ef\u80fd\u5c11\u201d\u3002
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答案:3+1/5.
解: (8/15)×(12÷2)=3+1/5.
4. 大圆半径为6厘米,小圆半径为4厘米,两圆中阴影部分面积之差等于______.解题技法大全P365_12
答案:62.8.
解: 大阴3.14×62-x; 小阴: 3.14×42-x
相减: 3.14×20=62.8.
5. 某种物品连续两次降价10%后,售价81元.那么这种物品的原价是________.
胡兴虎课课通六上P281_题2205
答案:100元.
解: 设原价为x, 则x×(1-10%)×(1-10%)=81, x=100.
二.计算题:
1. 名师辅导六年级周祥林P25拓展三
答案:1.
解: 19901990=1990×10001, 199019901990=1990×100010001.
19891989=1989×10001,198919891989=1989×100010001.
所以,原式=
==1.
2. 知识出版社 华罗庚奥林匹克教材六P11_例4
答案:1.
解:原式样=
三.几何题:
1. 下图是由6个相等的圆环组成,每相邻两个圆重叠部分的面积是2平方厘米,占每个圆面积的.这个图形的总面积是多少? 解题技法大全P367_2
答案:87+5/6.
解: 每个圆的面积: 17/6÷1/6=17.
17×6-17/6×5=87+5/6.
2. 如图,A与B是两个四分之一圆的圆心,那么,两个阴影部分的面积相差多少平方厘米? 杭顺清奥数教程六年级P65_16
答案:1.42.
解: 1/4×3.14×42-2×4-1/4×3.14×22=1.42.
四.解答题:
1. (7分)一只猴子摘了一堆桃子,第一天吃了这堆桃子的1/7,第二天吃了余下的1/6,第三天,第四天……第六天每天都吃了当时剩下的1/5,1/4,1/3,1/2.这时还剩下12只桃子,那么这只猴子摘的一堆桃子共有多少只? 杭顺清奥数教程六年级P164_例5
答案: 84.
解: 12÷÷÷÷÷÷
=84.
2. (8分)某商品按20%的利润定价,然后再按八八折卖出,共得利润16.8元,这件商品的成本是多少元? 周周练六年级P200_例3
答案:300元.
解: 16.8÷[(1+20%)×88% -1]=16.8÷5.6%=300.
3. (7分) 有一个蓄水池,池中有一根进水管和一根排水管,灌满一池水需打开进水管5小时,排光一池水需打开排水管2小时.现池内有满满一池水,有一个人按排水,进水,排水,……..的顺序轮流各开1小时,那么这个无聊的人在多长时间后看到池中的水刚好排完? 周周练六年级P103_14
答案:4+4/5小时.
解: 1小时后有水: 1-1/2=1/2;
2小时后有水: 1/2+1/5=7/10;
3小时后有水: 7/10-1/2=1/5;
4小时后有水: 1/5+1/5=2/5.
2/5÷(1/2)=4/5小时.
所以,4+4/5小时后水排完