Key words: How many soybeans are there in the third grade of primary school?

This article is suitable for: the third grade of primary school.

Composition source:

This composition is about the third grade of primary school. The topic is: "How many soybeans are there in one kilogram?" (with pictures), everyone is welcome to contribute enthusiastically.

How many soybeans are there in a kilo? (with pictures)

Fannier

I put some soybeans in a fresh-keeping bag and weighed out one kilogram of soybeans. I estimate that there are 5000 soybeans in one kilogram. Because, I first weighed one gram of soybeans with a balance, and there are five, so there are about 5000 soybeans in 1000 gram.

Method 1:

I divided1000g soybean into four parts. How many pills are there in one serving? My mother and I counted 10 10. Counting, one serving has 14 19 soybeans. So, one kilogram of soybeans has 4 *

14 19=5676 capsules.

Method 2:

I grabbed a handful of soybeans from1000g with one hand and counted them. * * * Yes 10 1. I catch the remaining soybeans one by one, 54 at a time. A handful has 10 1 soybean. Then, one kilogram of soybean has 54 * 10 1=5454.

Method 3:

I put some soybeans in the cup until it is full. I counted, * * * there are 858 pills. I poured that cup and replaced it with a new one. I changed it six times in a row, leaving more than half a cup. I guess it has 700 capsules. A cup of 858 pills, changed six times, and there are 700 pills left. Then, one kilogram of soybean is 6*858+700=5848.

Method 4:

I put some soybeans on the balance, weighed 20 grams of soybeans and counted them, *** 108. 20 * 50 =1000g, so one kilogram of soybean is 50* 108=5400 grains.

Activity overview:

In this activity, I found that the number of soybeans per kilogram ranged from 5400 to 5900, with an average of 5595.

Parental comments:

How many soybeans are there in a kilo? In this practical activity, Fanny tried a variety of estimation methods and exercised her ability to estimate the weight and quantity of objects. Method 1 ~ 4 is a method listed in mathematics textbooks, which does not depend on measuring instruments and estimates by grouping, counting and mathematical multiplication. Method 4: Weigh 20 grams of soybeans with a balance, then count them, and finally directly calculate the total number of particles. This method is relatively simple and accurate, but the first three methods without instruments are more suitable for training children's estimation ability.

There is mathematics everywhere in life. Let's discover the fun together!