Bài 1: Giải:

Từ 1 ⇒ 9 có số trang là : (9 - 1) x 1 + 1 = 9(trang)

⇒ Từ 1 đến 9 cần đánh số chữ số là: 9 x 1 = 9(chữ số)

Từ 10 ⇒ 99 có số trang là: (99 - 10) x 1 + 1 = 90(trang)

⇒ Từ 10 đến 99 cần đánh số chữ số là: 90 x 2 = 180(chữ số)

Từ 100 ⇒ 452 có tổng số trang là: (452 - 100) x 1 + 1 = 353(trang) 

⇒ Từ 100 đến 452 cần đánh số chữ số là: 353 x 3 = 1059(chữ số)

⇒ Vậy phải đánh tổng các số chữ số là: 9 + 180 + 1059 = 1248(chữ số)

Vậy người cần đánh 1248 chữ số.

Đ/số:.....

Bài 4: Bài giải:

Dãy số trên có tất cả các số hạng là: (2020 - 10) : 3 + 1 = 671(số hạng)

Đáp số: 671 số hạng

- I have subjects is music, art,Vietnamese and math on Wednesdays.

-I have English on Mondays

-It's math

-Because I want to be a math teacher

-Yes ,I was.

-My school is in the district

-There are twenty classrooms in my school.

-I like computeroom in my school

- My favorite subjects is music

-I have English on Mondays

-It's math

-Because I want to be a math teacher

-No,I wasn't

-My school is in the district

-There are twenty classrooms

-I like computeroom in my school

a á ớ

đọc thấy rối quá ạ

(em mới lớp 5 ạ)

chúc mn giải đc nha

4096576

Cô cho em 10 coin đi ạ

Cô cho em 10coin e xin cảm ơn trước 

Em chúc các thầy, các cô luôn mạnh khoẻ, tiền vào như nước, sống thọ 100 tuổi và chúc các thầy, các cô có ngày 20-11 vui vẻ ạ.

Em chúc các thầy, các cô luôn mạnh khoẻ, tiền vào như nước 

Em muốn nhận

coin thì đc bao nhiêu hả cô

Hi chúc mọi người có ngày quốc tế vui vẻ^^!

em cảm ơn ạ chúc mọi người có 1 ngày quốc tế vuiii vẻ nhaa

Living in a smart city brings many benefits and disadvantages. In this article, I will present some pros and cons of living in a smart city.

The first advantage of living in a smart city is convenience. Information and communications technology is integrated into urban systems, helping to provide public services more effectively. For example, through mobile applications, people can easily search for information about transportation, destinations, and entertainment activities. Furthermore, the smart traffic system helps reduce congestion and save travel time.

Another advantage of smart cities is energy saving and environmental protection. Advanced technologies are applied to manage and use resources effectively. For example, automatic lighting and temperature regulation in buildings help save energy. In addition, the use of smart public transport and self-driving cars helps reduce polluting emissions.

However, living in a smart city also has disadvantages. One of them is the issue of information security. With the widespread use of information technology, the risk of personal information insecurity and privacy violations increases. This requires strong security measures to ensure the safety of people's personal data.

Another drawback of smart cities is their dependence on technology. If technology systems fail or are attacked, public services could be disrupted. This poses challenges for maintaining stability and ensuring security of smart cities.

In short, living in a smart city brings many benefits such as convenience and energy savings. However, it is also necessary to pay attention to information security issues and dependence on technology. To make the most of the advantages and minimize the disadvantages, smart investment and management from city managers is needed.
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cdmmamdbvđn em

Là gì vậy cô? Em không hiểu cho lắm

Title: Proposal for a welcome Event for New Students

To: The School Board and Teachers

Date: September 20,2025

Prepared by: Class 11B

Introduction:

This proposal aims to organize a welcome event to greet new members joining our school community

Details about the idea/project:

The event will take place in the school playgroupd on October 5,2025. It will include ice-breaking games, group activities, and short performances by students

Goals and benefits:

The event helps new members feel more comfortable, encourages teamwork, and creates a friendly school environment

Conclusion:

We kindly ask the school leaders to consider and approve this proposal so the event can be successfully organized