"Addition and Subtraction of Whole Hundreds and Whole Thousands" PPT on Understanding Numbers Within Ten Thousands (Lesson 2)

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"Addition and Subtraction of Whole Hundreds and Whole Thousands" PPT on Understanding Numbers Within Ten Thousands (Lesson 2)

Part One: Learning Objectives

1. Enable students to initially learn the strategies of addition and subtraction estimation to solve problems according to specific situations.

2. Through the exchange of addition and subtraction of numbers within ten thousand, students will understand that appropriate estimation methods should be selected according to the specific problems to be solved and data characteristics, initially cultivate students' number sense and estimation awareness, and experience the diversity of algorithms.

3. In the process of solving problems, students can feel the connection between mathematical knowledge and daily life, and initially feel the value of estimation.

[Key Points] Learn to use addition and subtraction to estimate and solve problems, and experience the diversity of algorithms.

[Difficulty] Choose estimation methods to solve problems based on actual needs and cultivate estimation awareness.

PPT on addition and subtraction of hundreds and thousands, part 2: classroom analysis

Fill it out.

In this lesson we will learn to use estimation strategies to solve practical problems.

(1) The experimental primary school has 1021 students this year, about ( ) people.

(2) There is a distance of 492 meters from Xiao Ming’s home to the school, which is about ( ) meters.

(3) The price of a TV is 1,095 yuan, which is about ( ) yuan.

Is 500 yuan enough to buy these two items?

What do you know? What is the problem to be solved?

Know the prices of telephones and hair dryers.

I wonder if 500 yuan is enough to buy these two items?

To know whether 500 yuan is enough, you first need to know how much you have to pay in total to buy a phone and a hair dryer.

I want to add 358 and 218 to see if there is more than 500, but I don’t know how to calculate yet...

Do you think he's right?

358＞300 218＞200

300+200=500

Bringing 500 yuan is not enough!

I use estimation methods to solve problems!

I spent 500 yuan to buy a phone that cost more than 300 yuan, and I had less than 200 yuan left, which was definitely not enough to buy a hair dryer.

Even if the phone costs 300 yuan, 500-300=200, it is not enough to buy a hair dryer!

PPT on addition and subtraction of hundreds and thousands, part three: classroom exercises

1. Do the math.

(1) It costs about ( ) yuan to buy a pair of gloves and a coat.

(2) Buying a bicycle is about ( ) yuan cheaper than buying a coat.

236 yuan is about 200 yuan, 500-200=300 yuan!

186 yuan is about 200 yuan, 529 yuan is about 500 yuan, 200+500=700 (yuan).

2. Is 600 yuan enough to buy these two items? Is 700 yuan enough?

380≈400

270≈300

380+270≈700(yuan)

Oral answer: 600 yuan is not enough, 700 yuan is enough.

3. Changjiang Primary School has 289 students in the third grade and 314 students in the fourth grade. Approximately how many students are there in the third and fourth grades?

Analysis: There are 289 third-year students, about 300 people, and 314 fourth-year students, about 300 people. 300+300=600, so there are about 600 people in the third and fourth grades.

289≈300

314≈300

300+300=600

Oral answer: There are about 600 students in the third and fourth grades.

4. The auditorium in Chengguan Town has 3,000 seats, and the three primary schools in Chengguan Town each have more than 800 students. If students from these three primary schools come to participate in the event at the same time, can they sit down?

Analysis: More than 800 is close to 1,000, but less than 1,000. Then the total number of students in the three primary schools is close to 3,000, but less than 3,000, so they can sit down.

Oral answer: Can sit down.

When using estimation to solve practical problems, estimate the number in the question into a close thousand, a whole hundred, a whole ten, or a few hundred or tens according to actual needs, and then calculate.

Keywords: Free download of PPT courseware for mathematics in the second volume of the second grade of the People's Education Press, PPT download of addition and subtraction of hundreds and thousands, PPT download of understanding of numbers within ten thousand, .PPT format;

For more information about the PPT courseware "Understanding Numbers Within Ten Thousands, Addition and Subtraction of Hundreds and Whole Thousands", please click on the PPT Tag of Understanding Numbers Within Ten Thousands, Addition and Subtraction of Whole Hundreds and Whole Thousands.

"Adding and Subtracting Whole Hundreds and Whole Thousands" PPT on understanding numbers within ten thousand (Lesson 1):

"Adding and Subtracting Hundreds and Whole Thousands" PPT on Understanding Numbers Within Ten Thousands (Lesson 1) Part One: Learning Objectives 1. Enable students to flexibly choose appropriate methods to add and subtract whole hundreds and whole thousand. Operation. 2. Experience the form of calculation methods for addition and subtraction of whole hundreds and whole thousands..

"Adding and Subtracting Whole Hundreds and Whole Thousands" PPT on understanding numbers within ten thousand:

"Adding and Subtracting Whole Hundreds and Whole Thousands" PPT on Understanding Numbers within Ten Thousands Part One: Learning New Knowledge How much does it cost to buy a computer and a refrigerator in total? Use addition calculation: 1000 + 2000 = 3000 (yuan). 1 thousand plus 2 thousand is 3 thousand, which is 3000. A refrigerator is better than a computer...

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Update Time: 2024-07-01

This template belongs to Mathematics courseware People's Education Press Second Grade Mathematics Volume 2 industry PPT template

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