Math problems know the final answer, not what to do with columns

Commonly used methods for solving problems.

Mastering the steps is the first step in solving practical problems, and in order to master the skills and skills of solving practical problems, you also need to master the basic methods of solving practical problems. Generally, it can be divided into comprehensive method, analysis method, ** method, demonstration method, elimination method, assumption method, reverse deduction method, enumeration method, etc. The main purpose of introducing these methods here is to help students master how to think and how to open the door of their wisdom when they encounter practical problems.

None of these methods are isolated, and in actual problem solving, two or three methods are often used at the same time, and there are many problems that can be analyzed in one way or another. The problem is that after mastering the various methods, you can flexibly use them according to the quantitative relationship in the problem, and you must not memorize and mechanically apply the problem-solving method. 1.

Omnibus Law. Starting from the known conditions, according to the quantity relationship, first select two known quantities, put forward a question that can be answered, and then take the quantity as a new known condition, match it with other known conditions, and then put forward a question that can be answered, and so on step by step, until the required result is obtained. This is the integrated approach. In the process of applying the synthesis method, the known conditions of the application problem are decomposed into several simple application problems that can be solved in turn.

Thank you.

This is normal, and many people do.

If you want to do a math problem, you can list the formulas that you think are possible according to the question, and if you answer the point, you will have a few points, and then you can write the answer, and you can get 1 or 2 points.

<> estimate that I miscalculated. You do the math again.

Answer: This calculation is 42 5

The calculation process is as follows:

Just subtract it, 15m is unchanged, and the difference is 15*3 5-3 5=9-3 5=8 2 5

.09 cubic meters = (8) liters (90) milliliters [I don't know the column].

2. The volume of a cone is 63cm, the height is 3cm, and the bottom area is (63) cubic centimeters [is it wrong] [remove the 3 outside the brackets of the judgment, and change the cm to the cube of cm] column; 63/3*3

3. A cylinder and a cone are equal in height at the bottom, and if their volumes differ by 32 cubic decimeters, then the volume of the cone is (16000) cubic centimeters [memorized units] column; 32/2*1000

The ratio of 8 is (), and if you write another ratio to the ratio it composes, this ratio can be (12; 16）

5. The sum of the reduced bending number, the subtraction and the difference is 40, the cracking ratio of the minus and the difference is 3:2, and the subtracted number is (20) column; 40 2 minus is (12). 20*3+1 [branch]3

6. A kind of salt, according to salt and water 1:100 to prepare 8008 grams of this brine, salt (kg) is required. 8008 to 808 column; 808*1+100/1*1000