Every time I do a math problem, I basically learn a little bit and ask a little question

Homework, especially in high school and junior high school, don't do so many simple questions, do one or two difficult questions that are related to the chapter you learned, be sure to do it correctly, don't use too much straw paper, a question to stipulate the amount of straw paper you use, as little as possible, you can refine your own computing ability, difficult problems can open up your thinking, the difficulty of the problem mainly lies in the small details and the overall grasp of knowledge, you practice more, the thinking is flexible, the details of accounting are very clear, more effective than doing a lot of simple questions, but you must make it to make a number. And when you do it well, you will have a great sense of accomplishment and confidence.

What you explore by yourself is really your own! You can think for yourself first, if you really can't, you need your mother to give you a little guidance, you have to master the method, in order to get through the hundreds.

Learning is my own problem, I am a teacher's student, a child's father, a student's teacher, so, learning or not learning is related to me, my students, I will guide, this is the direction of learning now, my children's supervision, this is a father can do now, as a student, I will ask, ask the teacher is the best student, of course, you can't ask without thinking, to ask a class, a haven't seen, have seen to write down, may forget, but write down, You can watch it step by step, watch a little bit a day, until you remember, you can see a little more, it is good to see more, of course, the best is to learn and have fun with happy learning, time and efficiency are my best answers.

I wish you to find your own way of learning as soon as possible, maybe you just don't want to learn this, maybe you can learn something else, it's okay.

In the past two days, I saw a math problem in the second grade of primary school, for the second grade of primary school, it involves only addition and subtraction within 100 digits, the problem is very simple, but there is controversy, why has such a simple math problem attracted so many people's attention?

The topic is like this, Xiaoli is 7 years old this year, her grandfather is 48 years older than Xiaoli, and her mother is 36 years younger than her grandfather.

This kind of question is actually to examine the student's addition operation, grandpa's age = Xiaoli's age + 48, then 7 + 48 = 55, then grandpa's age is 55 years old, mother's age = grandpa's age - 36, then 55-36 = 19, then mother's age is 19 years old.

This is the student's answer, the calculation is correct, the logic is correct, why was it corrected? The student recalculated several times and got the same answer, so he cried and asked his parents what was wrong? Parents also had no solution, so they put the question on the post bar for help.

Some netizens said: "The student's answer is less description and explanation. There are also nets that think:

The student did not make a mistake in this question, and it should be that the teacher corrected it. Others shifted their eyes to their mother's age and questioned their mother's age, whose mother was 19 years old and Xiaoli was 7 years old, was it biological?

As long as you figure out the relationship between the two numbers, first calculate the age relationship between Xiaoli and grandpa, calculate the age of grandpa, and then the age relationship between mother and grandpa, calculate the age of mother, so as to get the answer, then, the student's answer is right, why was it wrong? What's wrong with this question?

I don't know how to do many math problems yet, but I believe that as long as I study hard, in the near future, no matter how difficult math problems are, I believe you can do it, so let's work hard to learn math together.

I didn't know how to do a lot of math problems in high school, I lost interest, and now I often dream about math.

Wrong First of all, your unit 1 didn't figure it out that it is the world's per capita freshwater resources, so you must not use the average freshwater resources Ah, there is 75% less It's not 75% This has to be seen clearly Your answer is very easy to check The world is definitely bigger than China's 2300*75% The more * smaller the amount is not correct The correct is to assume that the world's per capita freshwater resources are x, then x-2300=75%x x=2300 (1-75%)= 9200 It should be true.

You are: 75% of the world's per capita freshwater resources

It should be: 2300 (1-75%)

2^43*

2 9 = 512 is about 500

2 43=(2 9) 4*2 7=128*(2 9) 4 Substituting 2 9 into the approximate number 500 yields:

128*(500) 4=128*5 4*10 8 So the height of a piece of paper with a thickness of 43 folds is greater than:

6 * 128 * 5 4 = 768 * 625 = 480,000 (km), which is obviously greater than the distance from the earth to the moon (385,000km).

I believe it's because it's growing exponentially.

Let the thickness be d

Stack once = d*2

Stacked quadratic = d*2 2

Stacks n times = d*2 n

Stacked 43 times = cm is approximately equal to 385,000 km

Believe, 2 to the 42nd power.

This number is larger than 385000km.

Believe it, because it's a geometric growth, y= you can do the math.

There were x people in the classroom, but now there are x+2 people.

Then you can get the equation.

4/9*x+2)/(x+2)=9/18

Solve x=36

So now the classroom size is x+2=38 people.

There are x people in the classroom.

4/9x+2=9/19（x+2）

4/9x+2=9/19x+18/19

76/171x+2=81/171x+18/195/171x=20/19

x=36.A: There are 36 people in total.

There were x people in the classroom.

Original girl: 4x 9

Later girls: 4x 9 +2 = 9 (x+2) 1976x 9 +38 = 9 (x+2).

76x + 342=81(x+2)

342-162=5x=180

x=36 now: 36+2=38

Solution: If there were x people in the past, now x + 2 people.

4/9*x+2)/(x+2)=9/18

x=3636+2=38 people.

38 people turned out to be x people. 19 (four-ninths x+2) = 9 (x+2) Find x=36Now there are 38 people.

I think that if you are in junior high school and you have less homework, you can spend more time thinking about it, after all, it will be more impressive if you do it yourself. If the time is tight in high school, you can be flexible according to the situation: if you can't solve all the possible solutions to this type of problem, then it means that this question should be a skill question, study the answer and then write it down and ask the teacher, and then do a few more similar questions to remember the method.

Our teacher in the third year of high school asked that the answers were only used to check whether the answers were correct, not to replace our own thinking. Some answers are not the easiest and best solutions, and you need to think for yourself.

I think that for a question, the thinking time is half an hour (of course, if you have enough time, you can think about it for a while), and if you still have no ideas for more than half an hour, don't waste time. We need to spend our time where it's best to do it. This is especially true of mathematics.

Look at the answers decisively, don't waste time, and learn to be more efficient.