2012年湖北省武汉外校小升初数学模拟试卷(B)

2012年湖北省武汉外校小升初模拟(B) 2012年湖北省武汉外校小升初数学 模拟试卷(B) to the fuel tank in a timely manner, and to install gasket between the tank and lid, tighten all bolts evenly on the oil tank cover, should body checking, testing team, reset, filling a job completed. Throughout the work process to prevent oil spills or spills to the ground, the site requirements the used oil properly. 4.1.12.3 transformer drying 4.1.12.3.1 transformers need to be dried should be based on the synthetic analysis-judgment to determine field test data 4.1.12.3.2 If the transformer needs to be dry, the temperature must be monitored. 4.1.12. ... Clean on the inside wall before installation, explosion-proof membrane film should complete airway completely skewed on the tank cap, install the tilt direction according to the provisions of the factories, no special provisions, should be inclined to the conservator. 4.1.12.8 install 4.1.12.8.1 installation of dryer dryer lid rubber pads must be removed to make it smooth, generally in the middle of the lid with the right amount transformer oil filtration effect. 4.1.12.8.2 drying oil seal should be properly installed, the oil level should be above the oil level line. Relay and 4.1.12.9 gas 4.1.12.9.1 gas thermometers installed relays and thermometer installation should be tested or verified and qualified. 4.1.12.9.2 gas relay should be installed horizontally, should relay on both sides of the pipe axis is flat with the transformer tank cover, allows access to the reservoir at one end slightly higher. 4.1.12.9.3 transformer thermometer for transformer oil is injected on the top cover to seal it. 4.1.12.9.4 signal contact connection should be correct, as per drawing requirements. 4.1.12.10 insulating oil transformer oil 4.1.12.10.1 transformer must be tested after passing into the transformer. 4.1.12.10.2 oil from the tank bottom valve into the oil, add and oil should be injected through special valves for oil storage tank, oil 2012年湖北省武汉外校小升初数学模拟试卷(B) 参考答案与试题解析 一、计算题:(4小题，每小题8分) 1((8分)计算:(要求写出计算过程) ; ; ; ( 考点: 分数的四则混合运算;运算定律与简便运算;分数的简便计算;整数、分数、小数、百分数四则混合运算。 分析: (1)先根据积不变规律把算式中的因数都变成含有，然后再运用乘法分配律简算; (2)先约分，然后把带分数化成一个整数和分数相加的形式，然后运用加法结合律简算; (3)先计算第一个小括号里面的乘法，和第二个小括号里面的加法，然后再计算中括号里的除法，再运用 乘法分配律简算; (4)先算小括号里面的乘法，再算小括号里面的除法，然后算小括号里面的减法，再算中括号里面的减法， 最后算括号外的除法( 解答: 解:(1)， =， =×(++)， =×， =; (2)， =3+8+4+2+1， =(3+8)+(4+2)+(+)+1， =12+6++1+， =(12+6+1)+(+)， =19+， to the fuel tank in a timely manner, and to install gasket between the tank and lid, tighten all bolts evenly on the oil tank cover, should body checking, testing team, reset, filling a job completed. Throughout the work process to prevent oil spills or spills to the ground, the site requirements the used oil properly. 4.1.12.3 transformer drying 4.1.12.3.1 transformers need to be dried should be based on the synthetic analysis-judgment to determine field test data 4.1.12.3.2 If the transformer needs to be dry, the temperature must be monitored. 4.1.12. ... Clean on the inside wall before installation, explosion-proof membrane film should complete airway completely skewed on the tank cap, install the tilt direction according to the provisions of the factories, no special provisions, should be inclined to the conservator. 4.1.12.8 install 4.1.12.8.1 installation of dryer dryer lid rubber pads must be removed to make it smooth, generally in the middle of the lid with the right amount transformer oil filtration effect. 4.1.12.8.2 drying oil seal should be properly installed, the oil level should be above the oil level line. Relay and 4.1.12.9 gas 4.1.12.9.1 gas thermometers installed relays and thermometer installation should be tested or verified and qualified. 4.1.12.9.2 gas relay should be installed horizontally, should relay on both sides of the pipe axis is flat with the transformer tank cover, allows access to the reservoir at one end slightly higher. 4.1.12.9.3 transformer thermometer for transformer oil is injected on the top cover to seal it. 4.1.12.9.4 signal contact connection should be correct, as per drawing requirements. 4.1.12.10 insulating oil transformer oil 4.1.12.10.1 transformer must be tested after passing into the transformer. 4.1.12.10.2 oil from the tank bottom valve into the oil, add and oil should be injected through special valves for oil storage tank, oil www.mofangge.com =20; (3)， =， =， =(,)×， =×,×， =7,， =2; (4)， =， =， =， =， =8,， =( 点评: 此题是考查四则混合运算，要仔细观察算式的特点，灵活运用一些定律进行简便计算;还要注意本题中的 数字较大，计算较困难，要细心计算( 二、填空题:(9小题，每小题3分) 2((3分)如图1所示，4张扑克牌放在桌子上，小明把其中一张旋转180?后得到如图2所示，那么他所旋转的牌 从左起是第 一或第二 张( 考点: 旋转。 魔方格独家呈现to the fuel tank in a timely manner, and to install gasket between the tank and lid, tighten all bolts evenly on the oil tank c over, should body checking, testing team, reset, filling a job completed. Throughout the work process to prevent oil spills or spills to the ground, the site requirements the used oil properly. 4.1.12.3 transformer drying 4.1.12.3.1 transformers need to be dried should be based on the synthetic analysis-judgment to determine field test data 4.1.12.3.2 If the transformer needs to be dry, the temperature must be monitored. 4.1.12. ... Clean on the inside wall before installation, explosion-proof membrane film should complete airway completely skewed on the tank cap, install the tilt direction according to the provisions of the factories, no special provisions, should be inclined to the conservator. 4.1.12.8 install 4.1.12.8.1 installation of dryer dryer lid rubber pads must be removed to make it smooth, generally in the middle of the lid with the right amount transformer oil filtration effect. 4.1.12.8.2 drying oil seal should be properly installed, the oil level should be above the oil level line. Relay and 4.1.12.9 gas 4.1.12.9.1 gas thermometers installed relays and thermometer installation should be tested or verified and qualified. 4.1.12.9.2 gas relay should be installed horizontally, should relay on both sides of the pipe axis is flat with the transformer tank cover, allows access to the reservoir at one end slightly higher. 4.1.12.9.3 transformer thermometer for transformer oil is injected on the top cover to seal it. 4.1.12.9.4 signal contact connection should be correct, as per drawing requirements. 4.1.12.10 insulating oil transformer oil 4.1.12.10.1 transformer must be tested after passing into the transformer. 4.1.12.10.2 oil from the tank bottom valve into the oil, add and oil should be injected through special valves for oil storage tank, oil 分析: 本题主要考查了中心对称图形的定义，根据定义即可求解( 解答: 解:观察两个图中可以发现，所有图形都没有变化，所以旋转的扑克是成中心对称的第一张和第二张( 故答案为:一或第二( 点评: 当所有图形都没有变化的时候，旋转的是成中心对称图形的，有变化的时候，旋转的便是有变化的( 3((3分)在图形中，每个大正方形网格都是由边长为1的小正方形组成，则图中阴影部分面积最大的是 ? ((填序号) 考点: 组合图形的面积。 分析: 根据正方形的性质把不规则图形的面积可以看成是规则图形的面积的和或差，从而可得到图中阴影部分面 积最大的图形( 解答: 解:图中阴影部分面积分别为: ?的阴影部分的面积是:9,×(3×2+1×2+2×2)， =9,×12， =9,6， =3; ?的阴影部分的面积是:9,1.5×4， =9,6， =3; ?的阴影部分的面积是:9,(1+3)×1?2×2,2×1?2×2， =9,4,2， =3; ?的阴影部分的面积是:9,×(2×1+2×2+1×3+2×1)， =9,×11， =9,5.5， =3.5; 阴影部分的面积最大的是第四选项( 故选:?( 点评: 解答此题的关键是依据正方形的特点分别求出阴影部分的面积，即可比较面积的大小( 4((3分)有一个长方体，每个面上分别写上数字1、2、3、4、5、6，有3个人从不同的角度观察的结果如图所示，则这个长方体上，与写有数字“6”的面相对的面上写的数字是 3 ( 考点: 长方体的展开图。 分析: 从(1)分析3的对面应该是1、2、6;从(3)分析3的对面是4、5、6，故3与6对面( 解答: 解:从(1)分析3的对面应该是1、2、6， to the fuel tank in a timely manner, and to install gasket between the tank and lid, tighten all bolts evenly on the oil tank cover, should body checking, testing team, reset, filling a job completed. Throughout the work process to prevent oil spills or spills to the ground, the site requirements the used oil properly. 4.1.12.3 transformer drying 4.1.12.3.1 transformers need to be dried should be based on the synthetic analysis-judgment to determine field test data 4.1.12.3.2 If the transformer needs to be dry, the temperature must be monitored. 4.1.12. ... Clean on the inside wall before installation, explosion-proof membrane film should complete airway completely skewed on the tank cap, install the tilt direction according to the provisions of the factories, no special provisions, should be inclined to the conservator. 4.1.12.8 install 4.1.12.8.1 installation of dryer dryer lid rubber pads must be removed to make it smooth, generally in the middle of the lid with the right amount transformer oil filtration effect. 4.1.12.8.2 drying oil seal should be properly installed, the oil level should be above the oil level line. Relay and 4.1.12.9 gas 4.1.12.9.1 gas thermometers installed relays and thermometer installation should be tested or verified and qualified. 4.1.12.9.2 gas relay should be installed horizontally, should relay on both sides of the pipe axis is flat with the transformer tank cover, allows access to the reservoir at one end slightly higher. 4.1.12.9.3 transformer thermometer for transformer oil is injected on the top cover to seal it. 4.1.12.9.4 signal contact connection should be correct, as per drawing requirements. 4.1.12.10 insulating oil transformer oil 4.1.12.10.1 transformer must be tested after passing into the transformer. 4.1.12.10.2 oil from the tank bottom valve into the oil, add and oil should be injected through special valves for oil storage tank, oil www.mofangge.com 从(3)分析3的对面是4、5、6， 所以3与6对面; 故答案位:3( 点评: 此题属于典型的逻辑推理题，解答此类题的关键是通过题意进行分析，进而通过分析、推理，得出问题答 案( 5((3分)如图是一个数值转换机，当输入两个数据A、B时，输出的结果为C(如表是输入A、B数据后，数值转换机输出C的对应值(请你据此判断，当输入A值是2011，输入B值是9时，数值转换机输出的C值是 4 ( 输入 A 25 44 47 53 79 B 8 2 6 10 11 输出 C 1 0 5 3 2 考点: 数表中的规律。 分析: 通过观察，看出25除以8商3余数是1;44除以2商22没有余数，即余数是0;47除以6商7余数是5; 53除以10商5余数是3;79除以11商7余数是2;因此得解( 解答: 解:25?8=3…1， 44?2=22， 47?6=7…5， 53?10=5…3， 79?11=7…2; 所以当输入A值、B值后，数值转换机输出的C值是A除以B后的余数: 2011?9=223…4， 答:当输入A值是2011，输入B值是9时，数值转换机输出的C值是4; 故答案为:4 点评: 先找到规律，再根据规律求解( 6((3分)如表，各行中的图案是由两种不同的图案按一定的规律演变，…，根据这样的规律，则在第8行中“?”图案的个数是 21 ( 第一行 ? 第二行 ? 第三行 ? ? 第四行 ?? ? … … 考点: 数与形结合的规律。 分析: 观察图形可知，第一行有1个星，第二行有1个星，第三行有2个星，第四行有3个星，…，可以看出从第 3行开始，星的个数是前面两个数字之和，由此即可解答( 解答: 解:第一行有1个星，第二行有1个星，第三行有2个星，第四行有3个星，…，可以看出从第3行开始， 星的个数是前面两个数字之和， 魔方格独家呈现to the fuel tank in a timely manner, and to install gasket between the tank and lid, tighten all bolts evenly on the oil tank c over, should body checking, testing team, reset, filling a job completed. Throughout the work process to prevent oil spills or spills to the ground, the site requirements the used oil properly. 4.1.12.3 transformer drying 4.1.12.3.1 transformers need to be dried should be based on the synthetic analysis-judgment to determine field test data 4.1.12.3.2 If the transformer needs to be dry, the temperature must be monitored. 4.1.12. ... Clean on the inside wall before installation, explosion-proof membrane film should complete airway completely skewed on the tank cap, install the tilt direction according to the provisions of the factories, no special provisions, should be inclined to the conservator. 4.1.12.8 install 4.1.12.8.1 installation of dryer dryer lid rubber pads must be removed to make it smooth, generally in the middle of the lid with the right amount transformer oil filtration effect. 4.1.12.8.2 drying oil seal should be properly installed, the oil level should be above the oil level line. Relay and 4.1.12.9 gas 4.1.12.9.1 gas thermometers installed relays and thermometer installation should be tested or verified and qualified. 4.1.12.9.2 gas relay should be installed horizontally, should relay on both sides of the pipe axis is flat with the transformer tank cover, allows access to the reservoir at one end slightly higher. 4.1.12.9.3 transformer thermometer for transformer oil is injected on the top cover to seal it. 4.1.12.9.4 signal contact connection should be correct, as per drawing requirements. 4.1.12.10 insulating oil transformer oil 4.1.12.10.1 transformer must be tested after passing into the transformer. 4.1.12.10.2 oil from the tank bottom valve into the oil, add and oil should be injected through special valves for oil storage tank, oil 所以星星的个数依次可以排列为:1;1;2;3;5;8;13;21; 所以第8行中“?”图案的个数是21( 故答案为:21( 点评: 根据题干，找出星的个数排列特点，是解决本题的关键( 7((3分)找一下规律，从a，b，c，d，e中选入一幅图填入空格内(填代号)( a 考点: 数与形结合的规律。 分析: 观察方格内的图形可得:对角的两个图形形状相同，圆圈颜色是白色，三角形颜色一白一黑;由此即可选 择( 解答: 解:右下角的图形左边是白色三角形，右边是竖着的两个白色圆圈， 故答案为: 点评: 本题考查了图形的变化(解题的关键是发现各个角上图形的联系，找出其中的规律，有一定难度，要细心 观察总结( 8((3分)掷两枚质地均匀的骰子，将落地后正面朝上的数字相加得到一个新数，则这个新数最有可能是 7 ( 考点: 可能性的大小。 分析: 先例举展示所有36种等可能的结果数，数字相加得到一个新数，其中和等于7的有6种情况:(1，6)，(2， 5)，(3，4)，(4，3)，(5，2)，(6，1)，出现次数最多，即和最有可能是7;据此解答即可( 解答: 解:同时掷出出现的情况: (1，1)，(1，2)，(1，3)，(1，4)，(1，5)，(1，6)，(2，1)，(2，2)，(2，3)，(2，4)，(2，5)，(2， 6)，(3，1)，(3，2)，(3，3)，(3，4)，(3，5)，(3，6)，(4，1)，(4，2)，(4，3)，(4，4)，(4，5)，(4， 6)，(5，1)，(5，2)，(5，3)，(5，4)，(5，5)，(5，6)，(6，1)，(6，2)，(6，3)，(6，4)，(6，5)，(6， 6);共36种情况( 数字相加得到一个新数，其中出现(1，6)，(2，5)，(3，4)，(4，3)，(5，2)，(6，1)的次数最多，有6 次，即和最有可能是7; 答:则这个新数最有可能是7; 故答案为:7( 点评: 解答此题的关键是:先例举出所有出现的可能，进而从中找出出现和相等的次数最多的情况，继而结合题 意得出结论( 9((3分)如图所示:甲、乙两车沿两条互相平行的路线反向而行，在行驶过程中，甲车司机发现从甲车看乙车，视线总被路中央绿化带中的一棵树遮挡(已知甲车行驶路线距绿化带5米，乙车行驶路线距绿化带7米(则甲乙两车的速度比为 5:7 ( to the fuel tank in a timely manner, and to install gasket between the tank and lid, tighten all bolts evenly on the oil tank cover, should body checking, testing team, reset, filling a job completed. Throughout the work process to prevent oil spills or spills to the ground, the site requirements the used oil properly. 4.1.12.3 transformer drying 4.1.12.3.1 transformers need to be dried should be based on the synthetic analysis-judgment to determine field test data 4.1.12.3.2 If the transformer needs to be dry, the temperature must be monitored. 4.1.12. ... Clean on the inside wall before installation, explosion-proof membrane film should complete airway completely skewed on the tank cap, install the tilt direction according to the provisions of the factories, no special provisions, should be inclined to the conservator. 4.1.12.8 install 4.1.12.8.1 installation of dryer dryer lid rubber pads must be removed to make it smooth, generally in the middle of the lid with the right amount transformer oil filtration effect. 4.1.12.8.2 drying oil seal should be properly installed, the oil level should be above the oil level line. Relay and 4.1.12.9 gas 4.1.12.9.1 gas thermometers installed relays and thermometer installation should be tested or verified and qualified. 4.1.12.9.2 gas relay should be installed horizontally, should relay on both sides of the pipe axis is flat with the transformer tank cover, allows access to the reservoir at one end slightly higher. 4.1.12.9.3 transformer thermometer for transformer oil is injected on the top cover to seal it. 4.1.12.9.4 signal contact connection should be correct, as per drawing requirements. 4.1.12.10 insulating oil transformer oil 4.1.12.10.1 transformer must be tested after passing into the transformer. 4.1.12.10.2 oil from the tank bottom valve into the oil, add and oil should be injected through special valves for oil storage tank, oil www.mofangge.com 考点: 简单的行程问题。 分析: 甲车司机发现从甲车看乙车，视线总被路中央绿化带中的一棵树遮挡，又因为甲、乙两车沿两条互相平行 的路线反向而行，所以两车是匀速行驶，根据甲、乙两车行驶路线距绿化的距离，即可求出甲、乙两车的 速度比，就是它们距绿化带的距离比( 解答: 解:甲乙两车的速度比为5:7( 故答案为:5:7( 点评: 根据题意，理解甲、乙两车的速度比，就是它们距绿化带的距离比，是解答的关键( 10((3分)如图，第一个图形是一个水平摆放的小正方体木块，第二个图形和第三个图形是由这样的小正方体木块叠放而成，按照这样的规律继续叠放下去，若某个叠放的图形中，小正方体木块总数为153个，则这个图形是第 9 个图形( 考点: 数与形结合的规律。 分析: 图(1)中只有一层，有(4×0+1)一个正方形，图(2)中有两层，在图(1)的基础上增加了一层，第二 层有(4×1+1)个(图(3)中有三层，在图(2)的基础长增加了一层，第三层有(4×2+1)，依次类推当图 形有二层和七层时总的正方形的个数( 解答: 解:根据分析:当图形有二层时，第二层的正方形个数为:(4×1+1)，则此时总的正方形个数为1+(4×1+1) =6; 当图形有七层时，第七层的个数为:(4×6+1)，则此时总的正方形个数为:1+(4×1+1)+(4×2+1)+(4×3+1) +(4×4+1)+(4×5+1)+(4×6+1)=91( 当图形有8层时，第八层的个数为:(4×7+1)，则此时总个数是:1+(4×1+1)+(4×2+1)+(4×3+1)+(4×4+1) +(4×5+1)+(4×6+1)+(4×7+1)=120， 当图形有9层是，第九层的个数是:(4×8+1)，则此时总个数是:1+(4×1+1)+(4×2+1)+(4×3+1)+(4×4+1) +(4×5+1)+(4×6+1)+(4×7+1)+(4×8+1)=153， 答:当正方体的总块数是153时，这个图形有9层，是第9个图形( 故答案为:9( 点评: 本题考查了图形的变化规律，解题关键是根据图形的变换总结规律:每次都比上一次增加一层，增加第n 层时小正方形增加了4(n,1)+1个，将n层的小正方形个数相加即可得到总的小正方形个数( 三、解答题:(3小题，第11题6分，第12题7分，第13题7分) 11((6分)甲工程队有600人，其中老工人占5%;乙工程队有400人，老工人占20%(要使甲、乙两队中老工人所占的百分比相同，应在乙队中抽调多少名老工人与甲队中的年轻工人进行一对一的对换, 考点: 百分数的实际应用。 分析: 先把甲乙两队的总人数看成单位“1”，分别用乘法求出老工人的人数，进而求出老工人一共有多少人; 一对一的对换说明甲队和乙队各自的总人数不变，仍是600人和400人;老工人所占的百分比相同，那么 就把老工人的人数按照600:400的比例分配到两个队;再求出后来乙队的老工人数比原来少多少人，就是 应从乙队抽调的老工人数( 解答: 解:600×5%=30(人); 400×20%=80(人); 魔方格独家呈现to the fuel tank in a timely manner, and to install gasket between the tank and lid, tighten all bolts evenly on the oil tank c over, should body checking, testing team, reset, filling a job completed. Throughout the work process to prevent oil spills or spills to the ground, the site requirements the used oil properly. 4.1.12.3 transformer drying 4.1.12.3.1 transformers need to be dried should be based on the synthetic analysis-judgment to determine field test data 4.1.12.3.2 If the transformer needs to be dry, the temperature must be monitored. 4.1.12. ... Clean on the inside wall before installation, explosion-proof membrane film should complete airway completely skewed on the tank cap, install the tilt direction according to the provisions of the factories, no special provisions, should be inclined to the conservator. 4.1.12.8 install 4.1.12.8.1 installation of dryer dryer lid rubber pads must be removed to make it smooth, generally in the middle of the lid with the right amount transformer oil filtration effect. 4.1.12.8.2 drying oil seal should be properly installed, the oil level should be above the oil level line. Relay and 4.1.12.9 gas 4.1.12.9.1 gas thermometers installed relays and thermometer installation should be tested or verified and qualified. 4.1.12.9.2 gas relay should be installed horizontally, should relay on both sides of the pipe axis is flat with the transformer tank cover, allows access to the reservoir at one end slightly higher. 4.1.12.9.3 transformer thermometer for transformer oil is injected on the top cover to seal it. 4.1.12.9.4 signal contact connection should be correct, as per drawing requirements. 4.1.12.10 insulating oil transformer oil 4.1.12.10.1 transformer must be tested after passing into the transformer. 4.1.12.10.2 oil from the tank bottom valve into the oil, add and oil should be injected through special valves for oil storage tank, oil 80+30=110(人); 甲队人数:乙队人数=600:400=3:2; 110×=44(人); 80,44=36(人); 答:应在乙队中抽调36名老工人与甲队中的年轻工人进行一对一的对换( 点评: 解决本题的关键是理解:把老工人人数按照甲乙两队的总人数的比例进行分配，那么他们占甲乙两队的百 分比相同;在理解这一点的基础上求出老工人的总人数进行分配即可( 12((7分)甲、乙、丙三个班向希望工程捐赠图书(已知甲班1人捐6册，有2人各捐7册，其余人各捐11册;乙班有1人捐6册，3人各捐8册，其余人各捐10册;丙班有2人各捐4册，6人各捐7册，其余人各捐9册(已知甲班捐书总数比乙班多28册，乙班比丙班多101册(各班捐书总数都在400册与550册之间(问:每班各有多少人, 考点: 分数和百分数应用题(多重条件)。 分析: 由题目条件，甲班捐书最多，丙班最小，甲班比丙班多捐28+101=129(册)(又各班捐书总数都在400册 与550册之间，则丙班捐书不少于400册，所以甲班捐书在529,550册之间( 甲班人数不少于(人)，不多于 (人)，即甲班人数是50人或51人(由此验证:如果甲班有50人，则甲班共捐书6+7+7+11×(50,3)=537 (册)，推知乙班捐书537,28=509(册)，乙班有(人)，人数是分数， 不合题意(所以甲班有51人，甲班共捐书6+7+7+11×(51,3)=548(册)，推知乙班捐有(548,28,6, 8×3)?10+4=53(人)，丙班有(548,129,4×2,7×6)?9+8=49(人)( 解答: 解:甲班比丙班多捐:28+101=129(册); 因为丙班捐书不少于400册，所以甲班捐书在529,550册之间( 甲班人数不少于(人)， 不多于(人)， 即甲班人数是50人或51人( 如果甲班有50人，则甲班共捐书6+7+7+11×(50,3)=537(册)， 推知乙班捐书537,28=509(册)，乙班有(人)， 人数是分数，不合题意( 所以甲班有51人，甲班共捐书6+7+7+11×(51,3)=548(册); 推知乙班捐有(548,28,6,8×3)?10+4=53(人); 丙班有(548,129,4×2,7×6)?9+8=49(人)( 故答案为:甲班有51人，乙班有53人，丙班有49人( 点评: 完成本题要理清思路，根据所给的多个条件进行推理验证，从而得出结论( 13((7分)以下是一组选择题的答案:A、B、B、D、C、B、C、D、C、D、C、A、B、D、C、A、C、D、C、B、B(小东看到后突发奇想，用1代替A，用2代替B，用3代替C，用4代替D(得到这样一组数据:1、2、2、4、3、2、3、4、3、4、3、1、2、4、3、1、3、4、3、2、2(并对数据进行处理(现在请你帮助他完成以下操作: ?计算这组数据的平均数和中位数(精确到百分位) ?在得出结论前小东提出了几个猜想，请你帮助他分析猜想的正确性(在后面“横线”中打?或×) A、若这组数据的众数是3，说明选择题中选C答案的居多 ? B、若这组数据的平均数最接近3，可间接说明选择题中选C答案的居多 × to the fuel tank in a timely manner, and to install gasket between the tank and lid, tighten all bolts evenly on the oil tank cover, should body checking, testing team, reset, filling a job completed. Throughout the work process to prevent oil spills or spills to the ground, the site requirements the used oil properly. 4.1.12.3 transformer drying 4.1.12.3.1 transformers need to be dried should be based on the synthetic analysis-judgment to determine field test data 4.1.12.3.2 If the transformer needs to be dry, the temperature must be monitored. 4.1.12. ... Clean on the inside wall before installation, explosion-proof membrane film should complete airway completely skewed on the tank cap, install the tilt direction according to the provisions of the factories, no special provisions, should be inclined to the conservator. 4.1.12.8 install 4.1.12.8.1 installation of dryer dryer lid rubber pads must be removed to make it smooth, generally in the middle of the lid with the right amount transformer oil filtration effect. 4.1.12.8.2 drying oil seal should be properly installed, the oil level should be above the oil level line. Relay and 4.1.12.9 gas 4.1.12.9.1 gas thermometers installed relays and thermometer installation should be tested or verified and qualified. 4.1.12.9.2 gas relay should be installed horizontally, should relay on both sides of the pipe axis is flat with the transformer tank cover, allows access to the reservoir at one end slightly higher. 4.1.12.9.3 transformer thermometer for transformer oil is injected on the top cover to seal it. 4.1.12.9.4 signal contact connection should be correct, as per drawing requirements. 4.1.12.10 insulating oil transformer oil 4.1.12.10.1 transformer must be tested after passing into the transformer. 4.1.12.10.2 oil from the tank bottom valve into the oil, add and oil should be injected through special valves for oil storage tank, oil www.mofangge.com C、若这组数据的中位数最接近3，可间接说明选择题中选C答案的居多 × ?相信你一定做出了正确的选择(接下来，好奇的小东又对一组判断题进行了处理(用1替换?，用2替换×)然后计算平均数为1.65更接近2，于是小东得出结论:判断题中选答案×的居多(请你判断这个结论是否正确，并用计算证明你的判断( 考点: 平均数的含义及求平均数的方法;中位数的意义及求解方法。 分析: (1)把得到的这21个数据加起来再除以21就是这组数据的平均数;把给出的此组数据中的数按从小到大 (或从大到小)的顺序排列，处于中间的那个数就是此组数据的中位数; (2)平均数反映的是一组数据的特征，不是其中每一个数据的特征;中位数是指在此组数据中的数按从小 到大(或从大到小)的顺序排列，处于中间的那个数;而众数是指在此组数据中出现次数最多的那个数， 由此做出选择; (3)设判断题中选答案?的题数为n，题目总数为a，由平均数算法:=1.65，变形得:n=0.35a ,0.5a，故判断题中选答案×的居多( 解答: 解:(1)平均数:(1+2+2+4+3+2+3+4+3+4+3+1+2+4+3+1+3+4+3+2+2)?21， =56?21， ?2.67; 把此组数据按从小到大的顺序排列为:1、1、1、2、2、2、2、2、2、3、3、3、3、3、3、3、4、4、4、4、 4， 处于中间的数是3， 所以这组数据的中位数是3; (2)A、因为众数是指在此组数据中出现次数最多的那个数，所以A的说法是正确的; B、因为平均数反映的是一组数据的特征，不是其中每一个数据的特征，所以B的说法是错误的( C、因为中位数是指在此组数据中的数按从小到大(或从大到小)的顺序排列，处于中间的那个数，所以C 的说法是错误的( (3)证明:设判断题中选答案?的题数为n，题目总数为a，由平均数算法:=1.65，变形 得:n=0.35a,0.5a， 所以判断题中选答案×的居多，结论正确( 故答案为:?，×，×( 点评: 本题主要考查了平均数、中位数与众数的意义与求解方法( 本资料仅限于学习和教研使用,不得用于商业用途 ! 最权威、最新鲜的名校名卷,你想的都在这里,快来加入魔方格吧! 魔方格官方网站www.mofangge.com 魔方格独家呈现to the fuel tank in a timely manner, and to install gasket between the tank and lid, tighten all bolts evenly on the oil tank c over, should body checking, testing team, reset, filling a job completed. Throughout the work process to prevent oil spills or spills to the ground, the site requirements the used oil properly. 4.1.12.3 transformer drying 4.1.12.3.1 transformers need to be dried should be based on the synthetic analysis-judgment to determine field test data 4.1.12.3.2 If the transformer needs to be dry, the temperature must be monitored. 4.1.12. ... Clean on the inside wall before installation, explosion-proof membrane film should complete airway completely skewed on the tank cap, install the tilt direction according to the provisions of the factories, no special provisions, should be inclined to the conservator. 4.1.12.8 install 4.1.12.8.1 installation of dryer dryer lid rubber pads must be removed to make it smooth, generally in the middle of the lid with the right amount transformer oil filtration effect. 4.1.12.8.2 drying oil seal should be properly installed, the oil level should be above the oil level line. Relay and 4.1.12.9 gas 4.1.12.9.1 gas thermometers installed relays and thermometer installation should be tested or verified and qualified. 4.1.12.9.2 gas relay should be installed horizontally, should relay on both sides of the pipe axis is flat with the transformer tank cover, allows access to the reservoir at one end slightly higher. 4.1.12.9.3 transformer thermometer for transformer oil is injected on the top cover to seal it. 4.1.12.9.4 signal contact connection should be correct, as per drawing requirements. 4.1.12.10 insulating oil transformer oil 4.1.12.10.1 transformer must be tested after passing into the transformer. 4.1.12.10.2 oil from the tank bottom valve into the oil, add and oil should be injected through special valves for oil storage tank, oil