1, bear shoots balloons, 6 balloons in a row, 3 balloons in a row. It hit four balloons.

2. Dogs and monkeys take the train. One carriage has 6 seats, 20 puppies, 16 monkeys.

There are 48 rabbits going by boat. There are eight big ships, and two small ships are less than big ships.

Expand knowledge:

Methods of collecting information:

1, observation method:

It mainly includes two aspects: one is the observation of human behavior, and the other is the observation of objective things. Observation method is widely used, and it is often used in combination with inquiring and collecting objects to improve the reliability of collecting information.

People can collect data by observing things or phenomena. They can observe plants, animals and weather in nature, or observe behaviors and events in daily life. Record observed information, such as color, shape, quantity, etc. , and organize it into tables or charts.

2. Interview method:

Interviews are more likely to stimulate respondents' reactions, and the whole process is more enjoyable. People can collect data by communicating with others. They can interview family, friends, teachers or others and ask their opinions, preferences, experiences and so on. You can prepare some questions or survey forms, record the respondents' answers, and then sort out and analyze these data.

3. Experimental methods:

People can conduct simple experiments to collect data. They can design some experiments, such as testing the growth of different plants under different lighting conditions, or comparing the insulation effects of different materials. Record the process and results of the experiment, and then analyze the data.

4. Investigation methods:

Survey methods are generally divided into two categories: general survey and sampling survey; Design a series of questions, spread them in a large area through the internet, telephone or paper, and then recycle the questionnaire to derive specific information.

5. Experimental method:

Experimental methods can obtain information or conclusions that are difficult to obtain by other means through the experimental process.

6, literature retrieval method:

Document retrieval is the process of retrieving the required information from a large number of documents. Literature retrieval is divided into manual retrieval and computer retrieval.