Solutions to common application problems

Mastering the steps of solving problems is the first step to solve application problems. If you want to master the skills and skills of solving application problems, you need to master the basic methods of solving application problems. Generally, it can be divided into synthesis method, analysis method, graphic method, demonstration method, elimination method, hypothesis method, reverse deduction method, enumeration method and so on. The introduction of these methods here is mainly to help students master how to think and open their own doors of wisdom when they encounter application problems. These methods are not isolated. In practical problem solving, two or three methods are often used at the same time, and many problems can be analyzed in one way or another. The problem is that after mastering various methods, you can use them flexibly with the help of the quantitative relationship in the topic, and you must not apply the problem-solving methods by rote.

1. comprehensive method

Starting from the known conditions, two known quantities are selected according to the quantitative relationship, and the questions that can be answered are put forward, and then the obtained quantities are taken as the new known conditions.

Match with other known conditions, then ask questions that can be answered, and then deduce them step by step until you get the required results. This is a comprehensive approach. In the process of using comprehensive method, the known conditions of application questions are decomposed into several simple application questions that can be answered in turn. Primary school mathematics network

Example 1. A chicken farm shipped 1 month13,600 broilers, which doubled in February and decreased by 800 in March compared with the previous two months. How many broilers were shipped in March?

The idea of comprehensive method is:

Formula: (13600+13600× 2)-800.

=

( 13600+27200)-800

=40800-800

=40000 (only)

A: 40,000 units were shipped in March.

Another solution: 13600×(2+ 1)-800

= 13600×3-800

=40800-800

=40000 (only)

There is a pile of coal in the factory. The original plan is to burn 3 tons a day, which can be burned for 96 days. Due to the improvement of coal burning mode, 0.6 tons of coal can be saved every day, and it can be burned for several days more than originally planned.

The idea of a comprehensive method to solve this problem is:

Formula: 3×96(3-0.6)-96

=288÷2.4-96

= 120-96

=24 days

A: It can burn for 24 days longer than originally planned.

Save with your heart, don't think too much.

The problem in primary school is not difficult. ..