怎么教孩子数学比例
百分比的意思到底是什么呀？求数学专家解答？
百分比的意思到底是什么呀？求数学专家解答？
举个例子：5个苹果里有一个烂的，那么，相当于100个苹果有几个烂的，这就是求这些苹果的烂苹果的百分率：(1/5)×100％＝20％。
比的三种计算方法？
这道题解答如下：
比的三种计算方法是：
一、化简法，即化为最简比再计算比值。如8：24：14。
二、除法计算，将比例转换为除式，计算商即比值。如25：525÷55。
三、分数法计算，将比例转换为分数。如36：836/89/4。
比例计算公式？
比例的基本计算公式主要有四个：
两个内项的积等于两个外项的积；
交换内项或交换外项，等式仍成立；
同时交换两个比的项的位置，等式仍成立；
两个前项分别加或减去两个后项，或两个后项减或加两个前项，等式仍成立。
希望这个答案对你有用谢谢。
关于数学百分比的算法？
15000的百分之三是15000×3/100450,即是把15000分成100份后的3份是多少。当然1份是150，那3份就是150的3倍450了。
这可以做个比方，本村人口15000人，有200人外出打工，求100人中多少人去打工这就是
所占的百分率，其算法是200÷150000.0133得出的是叫打工人口占单位人口的数，若100个人是多少，当然是这个数的100倍等于1，33必须加%符号才能完整的说明，这个村子有1.33%人在外地打工。
有个别孩子始终都只能考三四十分，有什么方法能提高她的数学成绩？
在医学界有句话叫做“对症下药，方能药到病除”，同理在针对孩子学习成绩这方面来说也要“对症下药”，我用一下方面为您解答您的问题。
找准“病因”找到问题，“对症下药”
面对孩子成绩太差，一味地送进补课机构去补习，以为成绩就会变好，结果往往是差强人意的，所以小向老师认为，第一步家长要做的就是找到孩子的问题所在，弄清楚孩子到底是因为什么原因导致学习成绩不好的。是孩子智力问题还是某些知识点没有掌握牢靠，导致的成绩不理想，孩子数学成绩太差，往往出现在以下方面。
一、孩子先天不足
每个家长都不肯承认自己孩子先天方面不足，这可以理解，但是孩子成绩差都太多了，也就意味着孩子某一些方面确实不行，这时候小向老师建议家长带孩子去一些鉴定中心去测试一下自己孩子智力到底是个什么情况，自己心里也有个数，别人不可能达到这高度，你再怎么往上面举也是无用功！面对这种情况，小向老师建议家长找到孩子擅长的方面，感兴趣的方面去努力，那样结果会更好，例如著名散文家、学者朱自清1916年报考北京大学预科，数学只有0分，但是在语文方面的成就并不低，一代散文大家。所以当孩子某些方面不足的时候，就不必要求孩子是个全才，专注在某一方面就好了。
二、计算能力差
数学成绩差的孩子，十个有九个就是差在了计算题这方面，计算不过关，数学成绩是不可能有多好的，计算也分为以下几个方面。
1.口算
口算也称心算，是孩子数学在一年级二年级注重训练的基础课，可以说一二年级计算能力如何决定了三年级以后计算能力的好与坏，也间接决定了数学成绩的高与低。
训练口算的方法很简单，首先就是熟悉10以内加减法，20以内加减法，还有就是乘法口诀表。把这些都熟悉了，然后多多练习，那样数学口算能力才会有所提高。
2.笔算
数学笔算不过关，那肯定就是基本的原理，竖式格式没有到位，口算能力不过关等等，在笔算过程中应用的就是口算，所以先把口算练好再笔算，那样成绩就会变好。
三、应用题是个大问题
数学成绩不及格，毫无疑问应用题是绝对错了一大片的，然而应用题为什么会错呢？
1.读不懂题目
应用题是数学里面夹杂着语文知识在里面的，这很考验孩子的阅读能力，一般数学应用题读不懂的孩子，阅读能力基本不怎么样，语文成绩肯定也是不怎么样的。读不懂题目，原因可能是有些字不认识不理解其字意，再就是不理解句意了。题目都读不懂，怎么去读题呢？
2.不会抓关键词
小学生做应用题很简单， 在读题的时候要学会看问题，抓关键词，抓住主题，去掉多余的没有上面用的词，抓住关键词语，把题目简单化。
3.不会画思维导图
抓住了关键词语之后，就是要弄清楚主体之间的关系，画出一个思维导图，便于理解。
我是小向老师呀，咱们下次不见不散！
There is a saying in the medical circle that prescribe the right medicine to cure the disease. By the same token, it is also necessary to prescribe the right medicine in terms of childrens academic performance. I will use this aspect to answer your question.
Find the cause and find the problem, prescribe the right medicine to the case
In the face of their childrens poor grades, they blindly send them to tutorial institutions, thinking that their grades will get better, and the results are often not satisfactory, so Xiao Xiang believes that the first step for parents is to find out where their childrens problems lie. Find out what causes the childs poor academic performance. Is the childs intellectual problems or some knowledge points do not have a solid grasp, resulting in poor grades, childrens math scores are too poor, often appear in the following aspects.
First, children are born with congenital deficiencies.
It is understandable that every parent refuses to admit the congenital deficiency of his child, but the childs grades are too poor, which means that the child is really not good in some aspects. At this time, I suggest to the teacher that parents take their children to some appraisal centers to test their childrens intelligence. They also have a number in their own mind. It is impossible for others to reach this height. No matter how much you lift up, it is futile! In the face of this situation, Xiao suggested to the teacher that parents should find out what their children are good at and work hard in what they are interested in, so that the result will be better. For example, Zhu Ziqing, a famous essayist and scholar, applied for the preparatory course of Peking University in 1916, and he only got 0 in math. but the achievement in Chinese is not low, a generation of , when the child is insufficient in some aspects, it is not necessary to require the child to be a generalist, just focus on one aspect.
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Second, poor computing power.
Nine out of ten children with poor math scores are poor in the calculation problem. If the calculation fails, it is impossible to have a good math score, and the calculation is also divided into the following aspects.
1. Oral calculation.
Mental arithmetic, also known as mental arithmetic, is a basic course for children to pay attention to training in first and second grade. It can be said that how the computing ability of the first and second grade determines the good or bad of the computing ability after the third grade, but also indirectly determines the high and low math scores.
The method of training mental calculation is very simple, first of all, be familiar with addition and subtraction within 10, addition and subtraction within 20, and multiplication table. Get familiar with all these, and then practice a lot, so that the ability of math and mental arithmetic will be improved.
two。. Written calculation.
The math pen does not pass, it must be the basic principle, the vertical format is not in place, the ability of mental calculation is not in place, and so on. What is used in the process of written calculation is the mental calculation, so first practice the oral calculation and then do the written calculation, so the results will get better.
Third, the application problem is a big problem.
If you fail in math, there is no doubt that there is a lot of mistakes in the application problems, but why are the application problems wrong?
1. I cant read the title.
The application problem is mixed with Chinese knowledge in mathematics, which is a test of childrens reading ability. for children who do not understand general math problems, their reading ability is basically not good, and their Chinese grades are definitely not good. Can not understand the topic, the reason may be that some words do not understand the meaning of the word, and then do not understand the meaning of the sentence. How can I read the title if I cant understand it?
two。. Cant grasp key words.
Primary school students to do the application problem is very simple, when reading the problem should learn to look at the problem, grasp the key words, grasp the theme, get rid of the superfluous words that are not used above, grasp the key words, simplify the topic.
3. Cant draw a mind map.
After grasping the key words, it is necessary to find out the relationship between the subjects and draw a mind map that is easy to understand.